What is the difference between a cast wheel and an alloy wheel? Alloy wheels: magnesium or aluminum? Alloy wheels for VAZ

Wheels are an important part of a car's exterior. They can transform and improve your appearance vehicle.

Right choice will improve safety and quality of movement. The most popular are steel and cast or alloy wheels. Each option has its own advantages and is selected depending on operating conditions and goals.

Thanks to new rims, it is easy to change the exterior of the car, make it stylish and presentable. When it comes to choosing between cast and steel, several factors are taken into account.

Important criteria:

1. Strength - determines the load that the part can handle. Reliable discs do not deform or crumble when hitting an obstacle or other mechanical impacts.
2. Flexibility – the ability to reduce the load on the chassis during emergency situations.
3. Weight - the lower the number, the better the handling. It also affects the load capacity. If you reduce the weight of each wheel by 1 kg, the load capacity increases by 50 kg. Weight also affects fuel consumption, speed development, and smoothness of movements.

By studying the characteristics of tires, operating conditions, and the purpose of the car, it is easier to determine which wheels are better, steel or alloy. The latter are designed for driving on high-quality surfaces. Steel ones can withstand harsh conditions and are repairable.

Each type of disk has advantages. Stamped ones are the most common. They are installed on cars during assembly, mainly on budget models. The basis is steel. Using the stamping method, the elements are given the desired shape. The design consists of the disk itself and the rim, which are soldered and covered with enamel.

Positive characteristics:

• affordable cost, determined by ease of production;
• with strong mechanical impact, only deformation occurs that can be eliminated;
• It’s easy to change the appearance by putting on caps and changing the shade.

Disadvantages of stamping:

• heavy weight, which affects handling, load capacity, and fuel consumption;
• susceptibility to corrosion;
• outdated design.

When thinking about what to choose - cast or stamped wheels, it is worth considering that steel models compete due to practicality and minimal price. In addition, they are indispensable for beginners, who can easily ruin expensive die-cast modifications.

High-quality, stylish wheels make the car's exterior more attractive. Therefore, car owners often pay attention to die-cast models. The process of their production involves casting from aluminum; other light metals and durable magnesium alloys are also used. The choice of base and the subtleties of production affect the properties of the product.

Positive sides:

• light weight – increases transport characteristics, maneuverability, dynamics;
• bright design– determined by a manufacturing method that does not limit design possibilities;
• comfort increases, the load on the chassis decreases;
• strength, determined by the plasticity of the base material;
• corrosion resistance;
• provide ventilation of the brake assembly.

Choosing the best alloy wheels, disadvantages are also studied. They are represented only by a price that is higher in comparison with steel ones. Although cases of chips and cracks arising as a result of mechanical influences and impacts cannot be excluded. Thus, microcracks form in the structure, leading to damage.

When choosing, take into account the parameters alloy wheels. These indicators determine traffic safety, safety of tires, and factory characteristics of the car. Here it is important to take into account the requirements of the car manufacturer, indicating the optimal technical parameters for specific model. The marking of such rims includes many symbols - 6.5Jx15 H2 5/112 ET39 d57.1.

Let's study the parameters:

• 6.5 – landing width indicator, expressed in inches;
• J – there are also JJ, JK, and other letters representing technical data regarding the rim flange;
• 15 – diameter, indicated in inches;
• H2 (H, FH, AH, CH) – defines data on the design features of rim flanges, humps, which are made for tubeless tires and are necessary for proper installation;
• 5/112 – fastening parameters, where 5 means the required number of bolts, and 112 is the diameter of the placement;
• ET39 – offset indicator; as it decreases, the wheel protrudes more;
• d57,1 – defines parameters central hole, measured in mm.

When choosing which alloy wheels are better, it is important to study the permissible load parameters, especially for jeeps and heavy cars. Pay attention to the Max Load indicator. This is the permissible load.

Among all the brands on the market, it is difficult to choose a product that is suitable in terms of quality and cost.

Brands worth attention:

1. SCAD is a domestic company that produces high-quality products with excellent design. Production lines are equipped modern equipment. Supplies are provided for Volkswagen, Ford.
2. K&K is a domestic company, popular outside the country. Low pressure casting is performed here. The design and materials of the brand's models are guaranteed for life.
3. LSWheels is a company offering a wide selection of modifications and lines.
4. Rotiform is a brand that has recently appeared on the market. The palette of shades and bold style are impressive.

When looking for the lightest versions, you should pay attention to Alutec. The use of unique technologies allowed the manufacturer to create the most durable models. They are coated with a special coating that has a high level of anti-corrosion protection. When choosing a model, you can find out how much alloy wheels weigh. For 17-inch products, the average is 6.5 - 7.5 kg, and depends on the complexity of the design.

When thinking about the difference between steel wheels and light alloy wheels, it is worth considering that the requirements are lower. In the production of cast modifications, strict standards apply to ensure the production of high-quality products. Other bolts and nuts are used for installation. They differ in the length of the rod and the mounting area is larger.

The installation diagram is the same, but cast ones will require additional tightening after a short mileage. Steel wheels are easily restored; repairing cast wheels is a dubious procedure. The presence of microcracks is accompanied by the formation of new flaws; the accuracy of the parameters is also important; they are difficult to maintain.

The problem of choosing between steel and alloy wheels continues to cause a lot of controversy among car enthusiasts. Manufacturers add fuel to the fire by advertising their own products in every possible way for the purpose of sale. Therefore, stereotypes have been formed about the characteristics of products made from different metals that do not correspond to reality. Hence the purpose of this material - to tell how stamped, forged and cast wheels differ, how to distinguish them from each other and which ones are better suited under different operating conditions of the car.

Light alloy wheels

The name “light alloy” is given to these products due to the properties of the materials from which they are made. This is an alloy of light metals - aluminum and magnesium; titanium and copper are added to it in small quantities for strength and ductility. Hence the second name for such discs - titanium. There are 2 types of alloy rims:

• cast;
• forged (pressed).

These 2 groups of products differ from each other in manufacturing technology, performance properties and cost. To understand which ones are better, you need to look at disk production in more detail.

Note. Sales representatives often impose on motorists the opinion that, unlike cast products, forged rims are made from incredibly durable and expensive metals, almost platinum. In fact, this is a myth; the composition of the alloy for the manufacture of both groups of products is absolutely the same. Manufacturers can slightly change the ratio of base and additional metals in the melt at their discretion.

About production technology

As the name suggests, cast products are made by pouring molten metal into special molds (casting method). The sequence of technological operations looks like this:

1. Metals - ingredients are placed in an oven, melted and mixed.
2. The alloy is fed to the mold and poured into it with a special ladle.
3. After hardening, the workpiece is removed from the mold and moved for machining. In this case, the structure of the rim and spokes has already been formed, all that remains is to remove excess material around the edges and refine the holes for the bolts, as well as balance the disc.
4. The last stage is testing under certain speed and shock loads.

Reference. At factories of famous brands, the process is fully automatic mode Using CNC machines, even casting is performed by a robot. Manual labor is practically eliminated.

The name “forged” does not accurately reflect the production method of these discs, since they are not forged, but extruded from a heated alloy using high-power hydraulic presses. The manufacturing algorithm is as follows:

1. As in the previous case, an alloy is prepared in the furnace, from which cylindrical blanks are cast.
2. Each blank undergoes several pressing operations, where it is formed into a solid wheel rim without spokes or holes.
3. Products undergo 2 heat treatment operations - hardening (strengthens the alloy) and tempering to relieve internal stresses in the metal.
4. Using mechanical processing on a variety of machines, holes are made in the disks, the pattern of the spokes is cut out, excess material is removed from the edges and balancing is carried out.
5. Testing at critical loads is performed on special equipment.

Note. So the second myth is dispelled - that due to the manufacturing technology, forged wheels cannot boast of a varied design. On CNC milling machines, you can cut any, even the most complex, pattern into the body of the workpiece.

Pros and cons of cast products

The main advantage of wheels made from light alloy casting is their attractive appearance, making a car of any age and brand look much prettier. And the choice of products in terms of configuration and number of knitting needles is incredibly wide. This is the main reason prompting car enthusiasts to replace steel wheel rims with light alloy ones.

Other advantages are also important, but they are of a technical nature:

• the reduced weight of the products results in lower fuel consumption and improves vehicle handling;
• for the same reason, the acceleration dynamics of the car improves, and the braking distance is reduced;
• products are initially balanced due to production technology;
• long service life.

Of the listed positive aspects, only the durability and balance of alloy wheels is really noticeable when the car owner changes tires in a tire shop. The improvement in handling and acceleration dynamics can only be felt by an experienced driver, and the change in fuel consumption is so insignificant that it is completely unnoticeable (0.1-0.2 liters per 100 km). Therefore, the beauty of alloy wheels remains a priority, and only then their technical parameters are valued.

Now about the disadvantages:

1. The products are resistant to strong and sharp impacts. A crack appears in the thinnest place or where an air pocket has formed inside the metal. Manufacturers claim that casting cannot be repaired.
2. The price of the product is higher than that of stamped steel wheels. Due to price variations, the difference can range from 50 to 200%.
3. Cast rims cannot be used on minibuses and small trucks as they are not designed to withstand such loads.
4. Maintenance operations for such products at a tire shop (changing tires, balancing) are more expensive.

Reference. In the post-Soviet countries there are many workshops where specialists have become accustomed to soldering cracks in aluminum castings. But such a repair cannot be called complete, and restored discs cannot be installed on the front axle of the car.

Advantages and disadvantages of forged wheels

The significant and only drawback of forged rims is their high cost, which is 2-5 times higher than casting, depending on the manufacturer. But for this money you will get the following advantages:

• reliability and strength;
• durability, the pressed rim will last as long as the car itself;
• light weight of the product (even compared to casting), which improves the car’s behavior on the road and reduces fuel consumption.

Thanks to pressing and hardening in the manufacture of such rims, the metal does not have hidden holes and acquires increased strength, so cracks from impacts are an extremely rare occurrence. In addition, the spokes of the product can be made thinner and more openwork, giving the wheel design additional lightness and beauty. This is what you pay money for when you buy a forged wheel.

How to make cast alloy wheels - video

Stamped steel rims - the secret of popularity

More than 60% of all cars in the post-Soviet countries are equipped with disks made of sheet carbon steel. The vast majority of these cars are equipped with these wheels from the factory, since they are cheaper than others. Exceptions are cars in luxury configurations or luxury brands, for which the “stamping” frankly does not suit the appearance.

Despite their cheapness, iron wheels have many advantages:

• Compared to aluminum alloy, steel has ductility and elasticity, so the rim partially absorbs impacts when driving over large uneven surfaces;
• for the same reason, steel products are easy to repair - deformed areas can be straightened, and cracks can be welded;
• scope of application - transport of any purpose and carrying capacity;
• low prices for wheel maintenance;
• There are no problems with fastening the wheels, for which factory (standard) bolts are used.

The most valuable advantage when driving on our roads is the high maintainability of stamped wheels and the ability to absorb shocks. Combined with low cost, these features make traditional iron rims the most attractive in the eyes of ordinary users. To understand how their cost is formed, it would not hurt to familiarize yourself with the manufacturing technology of such products.

Production by stamping

Thick sheet steel is used to make iron rims. Two types of workpieces are cut from it - a circle and a strip, sent for further processing. The process looks like this:

1. On a hydraulic press, the core of the future disk with holes for bolts and technological openings is stamped from a steel circle.
2. The strip is sent to rollers, where it is bent into a cylinder shape. The ends of the sheet are welded together, after which the seam is cleaned.
3. A hydraulic press squeezes the finished rim out of the cylinder, then a hole for the valve is drilled in it.
4. Both elements are connected by welding, then covered with primer and painted.

In the manufacture of stamped products, expensive CNC machines and furnaces are not used, which is why energy costs are significantly lower. Hence the low price of the final product.

Video of the assembly process of stamped products

Weaknesses of steel wheels

Compared to attractive products made from light aluminum alloy, stamped iron rims are inferior in appearance, which often becomes the reason for their replacement. Plastic decorative caps, which always get lost on potholes on our roads, do not solve the problem, and the car owner has to buy new ones.

For reference. To prevent the hubcaps from flying off the wheels, many drivers fasten them to the rims with plastic electrical clamps. This helps, although it somewhat spoils the appearance of the car.

There are other negative aspects in using “stampings”:

• due to the large weight of the wheels, the car’s handling is worse and fuel consumption is higher;
• increased braking distance;
• products made of stamped iron cannot boast of good balancing;
• metal rusts and therefore requires maintenance.

Judging by the statistics, the listed shortcomings do not bother most Russian drivers too much. Again, some of the negative aspects are misinterpreted by sellers. For example, there is no basis for the statement that steel can rot in 2 years and the disk will become unsuitable for further use. To bring the metal to this state, it will take twice as long, and with timely care, the product will last no less than light alloy.

Note. There is a myth that the paint of stamped rims is easily scratched and quickly becomes unusable, but the light alloy surface cannot be damaged. The second part of the statement is incorrect; alloy wheels can also be scratched, but painting them is much more difficult.

Type selection rims it is better to fulfill according to three criteria:

• depending on the operating conditions of the machine;
• car class and make;
• active driving in cold or warm periods of the year.

Advice. If you expect to use one set of rims all year round, then, taking into account Russian road conditions, it is better not to risk money and install steel “stamping”.

The ideal option is to have 2 sets of discs, using them in the warm and cold seasons. For summer driving on asphalt surfaces, light alloy rims are perfect, but for the winter you need to use stamped ones. The problem is ice that appears on the asphalt due to unremoved snow, causing a smooth road to be covered with continuous potholes. The same ice along the edges of the roadway will easily scratch your beautiful titanium wheels when pulling onto the side of the road or approaching close to the curb.

When choosing a set of new disks, it doesn’t hurt to take into account other recommendations:

1. You shouldn’t shell out money and buy light alloy products if you drive an SUV across the fields. Conversely, luxury cars driven on smooth roads should not be stamped; it looks reprehensible.
2. Forged wheels are suitable for any passenger car and various driving conditions, except outright off-road.
3. Do not try to install alloy rims on a minibus that is used for commercial transport, you risk quickly making them unusable.

When choosing forged products, a natural question arises - how to distinguish them from casting when they are externally similar. After all, an unscrupulous seller can slip you a cheaper product at a price forged wheels. There are a number of tips on this matter:

1. Forging is easier than casting. For example, a forged rim measuring 15 inches weighs no more than 5 kg, and a cast one weighs 7-8 kg.
2. On pressed products processed by milling machines, you will not find burrs or small flash around the edges, as is the case with casting.
3. As a rule, inscriptions on cast wheels protrude above the surface, while on forged ones they are recessed because they are applied by extrusion.
4. If the product is branded and accompanied by documents, then in the specification of the forged rim you will find the corresponding English word- FORGED.

Advice. There are many exceptions to these rules, which appear when studying products from domestic or Chinese manufacturers. The best option is to buy forged rims in retail outlets with an impeccable reputation or from official dealers.

Despite the numerous advantages of alloy wheels, they cannot conquer even half of the Russian market. A similar situation is observed in the countries of the former USSR, where stamped products are more relevant and practical than aluminum ones. A change in trend should not be expected until there is a dramatic improvement in paved roads.

Disk types

Wheels are divided into two large groups: steel and made of light alloys.

1. Steel wheels
2. Alloy wheels

Steel wheels, or rather, their parts, are stamped from a sheet, and then these parts are connected by welding. It turns out to be extremely cheap and quite high quality - which is why the vast majority of cars on the factory assembly line are equipped with steel ones.

Advantages:

Low price;
+ quite high strength and the ability to recover even in the event of very strong crushing of the edges.

Flaws:

Large mass;
- low manufacturing accuracy (which means there may be problems with balancing) and outdated design;
- low corrosion resistance, largely due to the quality of the coating. At the same time, the lowest corrosion resistance is found in discs coated with enamel and electrophoresis.

Alloy wheels It has many properties better than steel. They allow any design play, they have the highest manufacturing precision, they perfectly remove heat from the brake unit, but most importantly, they are light (the lighter the discs, the lower the total mass of the unsprung parts of the car, which means the better). These are general advantages. It is possible to accurately judge their pros and cons only by taking into account how they are made and from what kind of alloy - there are many nuances here, every wheel is different.

According to the manufacturing method, light alloy wheels are divided into cast and forged.

Cast drive has a granular internal structure of the metal, and this is its main disadvantage: when driving over potholes for a long time, the process of accumulation of microcracks (invisible and therefore dangerous) occurs in the metal, which will sooner or later manifest themselves - the disc can split from a strong impact.

Flaws:

A cast disc requires serious surface protection; without this, it quickly becomes covered with a whitish oxide film and loses its presentation;
- the cast disc is quite fragile: with a very strong impact it splits, which high speed extremely dangerous. To ensure sufficient mechanical strength, the wall thickness has to be increased, and this reduces the much-desired weight gain.

Forged disc. Forging provides exceptionally high strength and rigidity of the structure. The forged disc withstands the strongest impacts; in extreme cases, it does not burst like a cast one, but bends without cracking, which is certainly safer. In addition, it is very lightweight. Compare: a stamped steel disk, for example, for the 7th BMW model weighs 9 kg, cast aluminum - 7.8 kg, and forged aluminum - 6.8 kg. It is theoretically possible to dent it, but the suspension will more likely fall apart than the edge of a forged wheel will dent.
The corrosion resistance of a forged disc is significantly higher than that of a cast disc, which means that the requirements for surface protection are lower. If it were not for the high cost due to the complexity of the technology, forged wheels would probably have supplanted all others long ago - for most characteristics, forged wheels have no equal.
Discs are cast and forged from aluminum and magnesium alloys. If you arrange alloy wheels in order “from minus to plus” based on purely technical parameters, then the row will be as follows: cast magnesium (light, but capricious, cracks quickly), cast aluminum (normal in terms of the totality of qualities), forged aluminum (durable and lightweight) and forged magnesium (super strong and lightweight). But when choosing disks, it is clear that not only technical parameters play a role. We advise you to immediately discard extremes: magnesium wheels, both cast and forged, are very rare; as a rule, they are made only to order for sports cars.

Disc markings.

The disk should indicate:

Trademark or manufacturer's name.
- Date of manufacture. Usually a year and a week. For example: 0407 means the disc was released in the 4th week of 2007.
- Wheel offset (some American companies for some reason ignore this requirement; Europeans always indicate the offset).
- SAE, ISO, TUV - mark of the regulatory body. The marking indicates that the wheels comply with international rules or standards (in Russian, OTK; many companies brand their products not with dry alphanumeric indices, but with birds, flowers and other art).
- A separate X-ray inspection mark (usually for cast ones, indicating the absence of internal defects - shells).
- MAX LOAD 2000LB - a very common designation for the maximum load on a wheel (indicated in kilograms or pounds). For example, maximum load 2000 lbs (908kg).

In addition, the disk may indicate:

PCD 100/4 - connecting dimensions;
- MAX PSI 50 COLD - means that for a given rim the tire pressure should not exceed 50 feet per square inch (3.5 kgf/sq.cm). The word COLD reminds you that the tire pressure should be measured when the tire is cold.
- Melt number.
- Method of production. If the disc is forged - FORGED. This inscription is not provided for by any standards; it is stamped on the disk solely for prestige.

Full size, according to which a specialist or you yourself can understand whether it fits this disk for this or that car. Scheme rim as follows: 6.5JxR15 ET33 4*98 D58.1.

6.5 is the rim width in inches. Standard range: 3.5; 4.0; 4.5; 5.0; 5.5; 6.0; 6.5 and 7.0 inches; Tuning, sports and off-road cars may have wider wheels.
The use of both too wide and too narrow rims (relative to the width of the tire profile) is undesirable: the design profile of the tire is violated (the sidewalls are either compressed by the edges of the rim or stretched on it), due to which its driving characteristics deteriorate - response to turning, resistance to slip , lateral stiffness. The permissible deviation of the rim width from the norm is 0.5-1.0 inches for discs with a mounting diameter of up to 14 inches; and 1.0-1.5 inches - for disks with a diameter of 15 inches or more. But it’s better, of course, to take the disk exactly under the tire.

J - deciphering these symbols is quite difficult. These symbols are service symbols; they are important not for the consumer, but for the manufacturer and seller. We will briefly touch on them only because, when included in the dimensional inscription, they attract the buyer’s attention and raise a lot of questions. Decoding - in catalogs. J - encoded information about the design features of the side flanges of the rim (angles of inclination, radii, roundings, etc.). Depending on the specific design, it may be written JJ, JK, K or L. H2 is encoded information about the shape of the annular projections (humps) on the rim flanges, which keep the tubeless tire from jumping off the rim. There are many designs of humps. There is a simple Hump H (Hump), double H2, flat FH (Flat Hump), asymmetrical AH (Asymmetric Hump), combined CH (Combi Hump)... Sometimes they do without humps; a special shelf SL (Special Ledge) is made on the rim, the parameters of which are adjusted so that the tire holds securely, without “clinging” to anything other than the edge of the rim.

15 is the mounting diameter of the rim in inches. Standard range for cars and SUVs: 10, 12, 13, 14, 15, 16, 17, 18 and 19 inches.

ET33 - wheel offset in millimeters. May be designated as OFFSET or DEPORT. This is the distance between the longitudinal plane of symmetry of the rim and the mounting (fitting) plane of the wheel. The offset can be zero, positive (the disc hub protrudes outward relative to the middle of the rim) and negative (the hub is recessed). For each car model, the offset is calculated so as to ensure optimal stability and controllability of the car, as well as the least load on the wheel bearings. The Germans designate the offset ET (for example, ET30 (mm), if its value is positive, or ET-30, if negative), the French - DEPORT, manufacturers from other countries usually use the English OFFSET.

Installing wheels with abnormal offset on a car:

Reducing the offset makes the wheel track wider; Although this slightly increases the stability of the car and gives it a “stylish racing look,” it also dramatically overloads the wheel bearings and suspension.

Increased reach, i.e. narrowing the track is, as a rule, impossible - the disc will rest against the brake mechanisms.

To install “non-original” disks with incorrect offset (but correct drilling), it is necessary to have a spacer between the mating plane of the disk and the hub - to correct the offset.

4*98 - PCD (Pitch Circle Diameter). Number 4 is the number of mounting holes for bolts or nuts. The wheel mounting holes are located at different diameters with tight positional tolerances relative to the central hole.

Since the mounting holes are made with a significant tolerance plus in diameter, you can make a mistake in choosing a PCD if it differs from the standard one by a couple of millimeters.

For example, a PCD98/4 wheel is often put on a hub with PCD100/4 (98 mm from 100 cannot be distinguished by eye). It is unacceptable. In this case, of all the nuts (or bolts), only one will be fully tightened; the remaining holes will “lead away” and the fasteners will remain untightened or tightened skewed - the fit of the wheel on the hub will be incomplete. While driving, such a wheel will “beat”, in addition, not fully tightened nuts will unscrew by themselves.

For discs with three mounting bolts (or nuts), to obtain the PCD value, the distance S must be divided by a factor of 0.8658.

4 hole PCD = S/0.7071		5 holes PCD = S/0.5878		6 holes PCD = S/0.5

There are discs with a large number of mounting holes, which is called double drilling. Double drilling 5x100/114.3 means that there are 10 holes on the disk, 5 of which are designed for drilling 100, and 5 for drilling 114.3. Such disks can be installed both on cars with dimensions 5x100 and on cars with disks 5x114.3.

D58.1 - Center hole diameter (DIA)

The diameter of the central hole, which is measured from the side of the mating plane, must correspond to the diameter of the landing cylinder on the vehicle hub. Precise matching of these dimensions ensures preliminary centering of the wheel on the hub, which facilitates the installation of bolts. Final centering is carried out along conical or spherical surfaces in the holes in the wheel disk mounting with bolts or nuts.

When purchasing “non-original” disks, the central hole may be larger than expected. Manufacturers of spare parts often make a hole of a deliberately larger diameter and supply the disk with a set of adapter rings, which allows it to be used on different models cars. In this case, the wheel is centered along the PCD.

When installing the wheel, tighten the fastening elements in the order shown in the diagram.

All disks are divided into two large groups: alloy wheels and steel wheels.
Steel disks, or rather, their parts, are stamped from a sheet, and then these parts are joined by welding. It turns out to be extremely cheap and quite high quality - which is why the vast majority of cars on the factory assembly line are equipped with steel ones. Their advantages include fairly high strength and the possibility of recovery even in the event of very strong crushing of the edges. The main disadvantages: large mass, low manufacturing accuracy (which means there may be problems with balancing) and outdated design.

Alloy wheels It has many properties better than steel. They allow any games with design, alloy wheels the highest manufacturing precision, they perfectly remove heat from the brake unit, but the main thing is that they are light (the lighter alloy wheel, the lower the total mass of the unsprung parts of the car, and therefore the better). These are general advantages. It is more precise to judge the pros and cons alloy wheels it is possible, only taking into account in what way and from what particular alloy they are made - there are many nuances here, the wheel is different.

By manufacturing method alloy wheels divided into cast and forged. A cast disk has a granular internal structure of the metal, and this is its main disadvantage: when driving for a long time over potholes, the metal begins to accumulate microcracks (invisible and therefore dangerous), which will sooner or later manifest themselves - the disk can crack from a strong impact. Forged metal, the metal of which has a multilayer fibrous structure, is extremely durable; It is not afraid of potholes, it will not crack under any conditions (forging provides the necessary ductility). It is theoretically possible to dent it, but the suspension will more likely fall apart than the edge of a forged wheel will dent.

Discs are cast and forged from aluminum and magnesium alloys. If you place alloy wheels in order “from minus to plus” in terms of purely technical parameters, the series will be as follows: cast magnesium (light, but capricious, cracks quickly), cast aluminum (normal in terms of the totality of qualities), forged aluminum (durable and lightweight) and forged magnesium ( super durable and lightweight). But when choosing disks, it is clear that not only technical parameters play a role. We advise you to immediately discard extremes: magnesium wheels, both cast and forged, are very rare; as a rule, they are made only to order for sports cars.
The price of magnesium ones can go over $1000 (piece).

Wheel rim markings

The wheel rim must be marked with the following: manufacturer's trademark, date of manufacture (week and year), heat number, permissible static load (kg or lb), stamp of the inspection body, separate X-ray inspection stamp (usually for cast ones) and, of course, standard size For example, 5.5Jx15H2 ET30 - what does this mean?

5.5 is the rim width in inches. Standard range: 3.5; 4.0; 4.5; 5.0; 5.5; 6.0; 6.5 and 7.0 inches; Tuning, sports and off-road cars may have wider wheels.

15 is the mounting diameter of the rim in inches. Standard range for cars and SUVs: 10, 12, 13, 14, 15, 16, 17, 18 and 19 inches.

J and H2 are symbols needed more by specialists. J encrypts information about the design of the rim flanges (can be JJ, JK, K or L). And H2 is the design code for humps - ring protrusions on the rim flanges that serve to reliably hold the tubeless tire on the rim (there are many variations: H, FH, AH...).

ET30 - wheel offset in millimeters. May be designated as OFFSET or DEPORT. This is the distance between the longitudinal plane of symmetry of the rim and the mounting (fitting) plane of the wheel (if these planes coincide, the offset is zero). You cannot take wheels with an offset that is not standard for your car. Reducing the offset (the wheel track becomes wider) can create additional stress on the wheel bearings and suspension. With an increased reach (the track narrows) alloy wheel may stick into the brake assembly. In general, all games with crashes are a delicate matter. On tuning and sports modifications it is changed, but this is done in conjunction with a number of other changes.

The diameter of the mounting holes is PCD (Pitch Circle Diameter). For example, PCD100/4 means that this diameter is 100 mm, and the number of holes is 4 (this, however, can be seen as such).

Besides, alloy wheel they are selected according to the diameter of the central hole (if the error is minus, you will not be able to put the wheel on the car) and according to the characteristics of the mounting holes: tightening the bolts (nuts) “to a plane”, “to a sphere” or “to a cone” - you can’t go wrong with this.

1. What types of discs are there?

According to the type of manufacturing, wheel rims are divided into stamped, cast, forged and prefabricated. The first two types are the absolute leaders in terms of prevalence, the third are the choice of enthusiasts, and the fourth are actually exotic, but within the framework of the material we will say a few words about them.

2. Stamped discs

Stamped discs are the most budget-friendly and easiest to manufacture type. Such discs are made from rolled carbon (“black”) steel by stamping separately the rim and the front part and then joining them by welding. After manufacturing, the discs are painted with enamel, which protects them from the aggressive external environment.

The main goal of stamped discs is to be cheap and simple, which they successfully do. It is these discs that are installed on the basic equipment of new cars, and are also purchased by car owners for whom it is not the appearance of the disc that is important, but only its functionality.

The main advantages of a stamped disc are its aforementioned low cost, as well as softness and maintainability. Softness and maintainability are interrelated characteristics: the fact is that, due to the material used and manufacturing technology, stamped discs retain the inherent ductility of metal. Thus, upon impact, such disks crumple, absorbing and absorbing part of the impact energy, and the damaged disk can subsequently be repaired, retaining most of its performance characteristics. Another advantage in this situation is the partial damping of the shock falling on the suspension: by deforming, the “stamping” slightly softens the blow and in some cases can save the suspension from breaking at the cost of its own integrity.

The stamped disc also has a lot of disadvantages. In part, the notorious softness can also be attributed to them, but the main complaints of the owners are related to the large weight and utilitarian design of such products, as well as their poor protection from the external environment. Weight is indeed the main scourge of “stamps”: it exceeds that of a cast disk by an average of 15-30%. This is more important than it might seem: after all, a large unsprung mass leads to a slight deterioration in dynamics and an increase in fuel consumption.

The appearance of stamped wheels should be considered their feature, and not a disadvantage - this is a purely utilitarian product, although there are stamped wheels with hints of design. Those for whom appearance is important can compensate for it with decorative wheel covers that fit over the “stamping”. This is also relevant because stamped wheels, as a rule, easily lose their presentation: defects in painting and damage to the enamel lead to the disc rusting, and an aggressive external environment only aggravates this process.

Brief summary: stamped disks are cheap, heavy and repairable, they are worth choosing if the appearance of the disk is not at all important to you, but it is important to spend as little money on it as possible, both when purchasing and in operation.

3. Alloy wheels

Alloy wheels, as the name suggests, are produced by casting into a pre-prepared die. Such wheels are also called light alloy wheels - this is fair, because, unlike stamped ones, they are made not of steel, but of lighter alloys: as a rule, aluminum, and in the case of expensive products - magnesium and titanium. After manufacturing, the discs can be additionally painted, polished or varnished.

The main advantages of a cast disk are lower weight compared to stamped ones, significantly greater strength, corrosion resistance, as well as a much more aesthetic and varied design. In this case, everything is clear with the mass: it is less due to the use of lighter material. Higher strength and corrosion resistance are also a consequence of the materials used and manufacturing technology: a cast disk can withstand much greater loads without deformation and does not rust even if the surface is damaged. Well, the appearance depends solely on the matrix used, and this allows you to create many thousands of options for the appearance of the disk. The appearance is complemented by coloring: often a disc of the same design exists in different colors.

The disadvantages of a cast disk are low ductility and resulting fragility, high cost and difficulty of repair, as well as the higher price of the disk itself. Fragility – back side strength: a cast disk can withstand a stronger impact than a stamped one, however, if the force of the impact exceeds the capabilities of the disk, it will not only be dented, but will most likely crack or split. In addition, the strength of the alloy wheel means that the impact is fully transmitted to the vehicle's suspension.

Technologies for repairing such discs, of course, have been mastered, but this repair itself is prohibited by the Technical Regulations of the Customs Union, paragraph 5.7.2 of which states that “the presence of cracks on the discs and rims of wheels, traces of their repair by welding” is not allowed. This is a completely justified measure: the loss of performance characteristics during a potential repair is significant, and it is unknown how the repaired disk will behave in the future.

Quick summary: Alloy wheels are beautiful, light and strong, and worth choosing if you want the best balance of performance for your money.

4. Forged wheels

Forged wheels are the “elite” of the mass market. They are made from light aluminum alloys containing magnesium and titanium by die forging and subsequent machining. The workpiece, stamped at high temperature, retains the internal structure of the metal, and the design of the disk is usually determined on a milling machine.

The main advantages of a forged wheel are its outstanding lightness and strength, combined with the beauty of the product. The manufacturing technology ensures even less weight and even greater strength compared to casting - which is why forged wheels are considered best choice for the car enthusiast. Another important property of “forging” is ductility: with a critically strong impact, it does not crack, but creases, which makes recovery a little easier.

The main disadvantage of a forged wheel is that you have to pay well for all its advantages, at all stages and not only in money. The manufacturing technology of “forging” is the most complex, and this limits the number of manufacturers who do this. Accordingly, forged wheels are not only expensive, but also very rare: before you pay, you will have to look for them or order them. Well, another related problem is a large number of fakes: a large part of the “forging” on the market are alloy wheels with fake markings, and it is difficult to distinguish a cast wheel from a forged one.

Quick summary: Forged wheels are beautiful, very light and very durable, and are worth choosing if you want the best performance product and are willing to pay good money for them.