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What is the difference between alloy steel wheels? Wheel rims - types, markings. Cast magnesium wheels


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 The main disadvantages: large mass, low manufacturing accuracy (which means there may be problems with balancing) and outdated design.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.

Good afternoon, dear reader.

A car wheel consists of two parts: a tire (tyre) and a rim.

Features of installing rubber were discussed in the article "".

Today we will talk about rims. You will learn the differences between cast, stamped and forged wheels, as well as the features of selecting wheels for a specific car:

A short explanation for novice car enthusiasts. Wheel rim- this is the central metal part of the wheel on which the tire is mounted.

How to choose wheel rims according to parameters?

The ability to install a disc on a specific car is determined by several numerical parameters.

For example, a disk characteristic might look like this:
7 J R17 PCD5 *112 ET45 d57.1

As a rule, car manufacturers provide recommended wheel rim specifications. The car suspension is designed for wheels with certain parameters. Therefore, if you want to avoid possible problems in the future, then find disks that all 6 characteristics of which correspond parameters specified by the car manufacturer.

Let me note that in practice, when purchasing rims, the following may arise: problem. Wheels from official dealers are more expensive than similar wheels in specialized stores that sell tires and wheels. However, discs from dealers strictly comply with the recommended parameters, and discs in car dealerships may differ in one or more characteristics. What to do in this case?

1. Buy expensive wheels from a dealer and don’t worry about their parameters.

2. Try to find wheels that strictly comply with the required parameters in auto stores. You will have to spend a little more time on this task, but it is quite possible to solve it.

Unfortunately, the probability of finding disks with the required characteristics in the first store you come across is quite small, because... There are a huge number of different combinations. However, there is always the opportunity to order a suitable option through an online store, where there are no problems with the assortment.

3. Buy discs that differ in one or more parameters.

For example, you can buy discs of larger or smaller diameter. You can buy wheels that have a larger center hole, a different offset, or a wider width.

The only parameter that cannot be changed is PCD, because... The mounting holes of the disk must strictly correspond to the mounting holes on the car.

Let me emphasize once again that the use of disks with parameters different from those recommended can lead to technical malfunctions of the vehicle. So approach the issue wisely.

Let's return to the rims. On average, smaller drives cost less than larger drives.

For example, in practice it may be cheaper to buy winter tires and an additional set of 16-inch wheels than a set of 17-inch winter tires without wheels.

Note. In the text of this article, for comparison, prices for 14-inch wheel rims that are current in 2019 will be given.

Stamped steel wheels

The most common type of rims are stamped steel rims. Their popularity is largely due to their low cost (for 14-inch in the region of 1,200 - 2,000 rubles per disk).

A significant contribution to the spread of stamped wheel rims is made by the fact that many new cars in basic configurations are sold with such rims. Well, owners are in no hurry to spend money on new disks and use existing ones.

Advantage steel rims is their reaction to impacts (on). In this case, stamped discs usually do not crack, but bend. After this, the damaged disk can be restored and will serve for quite a long time.

Disadvantage steel rims is their heavy weight. Also, the disadvantages of stampings include their appearance. All stamped wheels are very similar to each other (an example is shown in the figure above) and are not particularly loved by car owners.

The problem of the appearance of stamped discs is solved by installing wheel covers, covering the disc and giving it an individual look.

Cast alloy wheels

Another popular type of rims is alloy wheels.

Unlike stamped wheels, which are made of steel, cast wheels are made of aluminum or magnesium alloy. In this regard, light alloy wheels are lighter, which is their significant advantage. Also, alloy wheels have greater thermal conductivity and this contributes to better heat removal from the brake mechanisms.

The manufacturing technology of light alloy wheels allows them to be given almost any shape. Therefore, in practice, alloy wheels look more attractive than their stamped counterparts.

Disadvantage light alloy wheels is their relatively high price (for 14 inch 3,000 - 4,500 rubles per disk). The second disadvantage of alloy wheels is that if the wheel falls into a large hole, the wheel rim may crack. It is impossible to restore a split disk; it must be completely replaced.

Nevertheless, alloy wheels find many supporters.

Forged wheels

Manufacturing technology forged wheels differs from the two previous types of disks.

Advantages Such discs are manifested in their high strength. In addition, forged wheels are the lightest.

Another undeniable advantage of forged wheels is that, unlike cast wheels, they do not split when they fall into a hole. From this advantage follows one of shortcomings forged wheels. Since forged wheels can easily survive falling into a hole, almost all of the impact energy is transferred to the suspension, which adversely affects the condition of the car.

The second disadvantage of forged wheels is that the design of such wheels is limited by their manufacturing technology.

Forged wheels cost about the same as cast wheels (3,000 - 4,500 rubles per disk for 14-inch wheels). Therefore, they have both supporters and opponents.

Let's summarize this article:

  • When choosing rims, you need to take into account the parameters recommended by the car manufacturer.
  • There are 3 types of rims.
  • Stamped wheels are the cheapest and heaviest. They can be repaired.
  • Alloy wheels are more expensive and lighter. They may break if they fall into a hole.
  • Forged wheels have the lowest weight and the greatest strength. Their use may damage the vehicle's suspension.

Good luck on the roads!

Before moving on to a description of production technologies, we note that the so-called “casting” has a large number of advantages. Moreover, they are placed in opposition not only to iron stamping, but also to forged products, which are traditionally considered one of the most durable and strong.

Only benefits

If we talk about the advantages of “casting” in relation to “forging”, it should be noted that they have a more affordable cost. Among imported products it can reach hundreds of percent. Of course, on the domestic market today you can find products from Russian enterprises that in the past were focused on meeting the needs of the defense complex. These forged wheels are relatively inexpensive. But even they cannot compete with “casting” in price.

In relation to stamped iron disks, cast “wheels” look even more preferable. Their advantages compared to steel stamping are as follows:

  • Light weight. This is perhaps the main advantage of light alloy casting. As a result, the load on the chassis is significantly reduced, the dynamic performance of the vehicle is improved, and fuel consumption is reduced. In addition, the passive safety of the car is significantly increased, due to the fact that contact with the roadway when hitting an obstacle is restored much faster. This improves handling.
  • Attractive design. To be absolutely precise, the design may be different. Choosing a specific model is a matter of taste and personal preference. But the main thing is that it simply exists. Unfortunately, this cannot be said in relation to iron stamping.
  • Finally, it is impossible not to note the practicality of such a solution. Alloy wheels do not require any special care. They do not rust and do not need to be painted. To maintain proper appearance, it is enough to wash them periodically and simply wipe them with a cloth.

A little negative

When discussing the advantages of "casting", it would be unfair not to mention its disadvantages. But they exist. This is, among other things, the fragility of the disk. The fact is that the alloy receives a free, non-directional crystalline structure during the casting process. This negatively affects its strength. Of course, we are not talking about problems in everyday use. But when hitting an obstacle at high speed, mechanical damage is possible, which, moreover, is difficult to repair. Although in modern conditions of wheel rim production this circumstance is gradually losing its relevance. Thanks to the use of low-pressure casting technology, as well as casting parts with back pressure, this disadvantage is leveled out. Therefore, when choosing, we recommend paying attention only to high-quality products manufactured under well-known brands and certified in Russia.

How are alloy wheels made?

Modern casting technologies involve the use of special molds for pouring metal alloys. The metal in the mold cools down, but the processing of the workpiece does not end there. Afterwards, the part is placed in a chamber heated to several hundred degrees (usually the temperature is maintained at 500 degrees Celsius). Heat treatment alternates with sudden cooling of the part. This process is called hardening and allows you to achieve a uniform metal structure. In addition, in order to bring the physical properties of the metal closer to structural equilibrium, during the manufacture of disks, an artificial aging stage is provided. It involves heating and holding the part for 5-6 hours at the phase transformation temperature (about 150-220 degrees), after which the disk is cooled under atmospheric conditions. The final links in the production process chain are mechanical processing and painting.

Aluminum in the production of cast wheels

One of the most popular types of raw materials used for the manufacture of cast wheels is aluminum, to which the necessary components are added (usually silicon is used as an additive). The advantages of this design solution are obvious:

  • Firstly, aluminum is a relatively inexpensive metal.
  • Secondly, it is a material that has a low specific gravity, since the density of aluminum is only 2.7 g/cm3.
  • Finally, this type of metal is not subject to corrosion, which significantly increases the service life of finished products. This effect is achieved due to the ability to form a strong oxide film of Al2O3 on the surface.

Finally, it should be noted that aluminum has extremely low thermal conductivity. This makes it possible to achieve better cooling of the vehicle's brake parts. In combination with the high precision of manufacturing wheel rims from aluminum alloys with silicon and other components, all of the factors listed above are the undeniable advantages of “casting” in this category.

As usual, not a single barrel of honey is complete without a fly in the ointment. Now about the disadvantages: this is, first of all, the low level of plasticity of the material. Thus, due to significant impact loads, aluminum wheel rims do not bend, but crack. That is, they cannot be repaired.

A few words about the benefits of magnesium

Magnesium is often used as an alternative to aluminum in the production of alloy wheels. As a rule, alloys based on this metal also contain aluminum, but its share is insignificant. The main advantage of magnesium disks is their extremely low weight, because the density of the metal is only 1.7 g/cm3. In addition, this type of material is characterized by high specific strength. According to the above properties, magnesium definitely outperforms cast aluminum. In all other respects, they are not inferior to them. But magnesium has one not very good property - alloys based on it are unstable to aggressive environments and are susceptible to corrosion. To eliminate this problem, manufacturers prefer to use multilayer coatings.

Instead of an afterword

Returning to the original formulation of the question “magnesium or aluminum”, we can say that there is no clear answer to it. It all depends on the specific operating conditions of the car. If you are choosing wheels for “every day” driving, then it is advisable to give preference to the more practical aluminum. If you plan to technically fine-tune the car while simultaneously improving dynamics and other characteristics, then you should pay attention to magnesium.

Wheels are an important part of a car's exterior. They are able to transform and improve the appearance of a vehicle.

The 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.

When choosing the best alloy wheels, you also study the disadvantages. 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 of 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 a particular 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 – determines the parameters of the 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. The production lines are equipped with 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.

Wheels are an integral part in the design of any car, which cannot be imagined without this part. A car without them, just like without an engine, simply won’t go. The traction force that ensures the vehicle moves occurs when torque is supplied from the engine to the drive wheels. The importance of this component of the vehicle becomes obvious. Wheel rims are divided into two large groups: those made of light alloys and steel. In this article we will talk in more detail about the first type.

Alloy wheel: options

Despite the fact that alloy wheels entered the automotive industry relatively recently, they, along with traditional “stamps,” have managed to take a strong position. In the manufacture of alloy wheels, materials such as magnesium and aluminum are used, but according to technology they are divided into forged and cast.

Cast aluminum wheels

These wheels are currently the most common type. They are made by casting from light alloys based on aluminum. Their advantage compared to steel wheels is their lighter weight, namely, they are 20-30% lighter. This is their main advantage. This factor significantly affects the dynamics of acceleration, smoothness, as well as fuel consumption. It is noted that the lighter the disc, the better the car’s handling becomes.

In addition, the wear of parts of the chassis system is reduced as a result of less load. Also, importantly, thanks to the use of aluminum, the aggressive impact of the environment on wheel rims will be significantly lower than on steel ones. This happens because an oxide film forms on the surface of the aluminum, and in order to prevent the appearance of the wheels from deteriorating due to this, paint and varnish material is applied to them. In general, such an alloy wheel has an attractive appearance and excellent performance parameters, and there is also the possibility of a wider choice regarding its external design. Despite most of the advantages, it also has a number of disadvantages compared to steel.

Cast magnesium wheels

Discs made of magnesium alloys are much less common. These wheels first appeared in 1980 on the Alfa Romeo Spider. If such rims are installed on a car, then in their manufacture, in addition to magnesium, as a rule, aluminum and some other metals are also used. Compared to aluminum rims, these rims are lighter, and perhaps this is their only advantage. They have a rather significant disadvantage - they have low corrosion resistance, for this reason such wheels require careful care and the use of special protective equipment.

Repair of alloy wheels

If such a light-alloy wheel has been subjected to deformation, then it will no longer be possible to use rolling with preheating to restore it; in this case, the removal of dents will need to be carried out on a special stand. If cracks occur, argon-arc welding is used. It should be noted that deformations of the cast disk occur quite rarely, because for this to happen, a great force must be applied to it. For comparison: in order for damage to occur on a wheel made on a light alloy base, an impact force 3-5 times greater than that under the influence of which a stamped steel disk is deformed will be required. But there is also a disadvantage, which is that alloy wheels are practically impossible to repair, but forged ones, along with stamped ones, are quite easy to restore.

Forged wheels

These rims are made, as a rule, by hot stamping of a light alloy billet. In their manufacture, different shapes are used than steel wheels, and the alloys are also subjected to higher temperatures. Such discs are obtained with thinner walls, but their density is much higher than that of cast discs. The material becomes more elastic, thus resembling the properties of steel discs, and at the same time the product is significantly lighter. It is worth noting that the materials used are the same as in the production of alloy wheels, the only difference is in the technology. These are the most expensive “skating rinks”, since high-quality equipment is used in their production.

Difference between cast and forged wheels

If we compare these two options, we can say the following: forged wheels are stronger than their counterparts, since cast wheels have increased grain size, and accordingly, they can get cracks as a result of impacts. In general, they are more suitable for traveling on good roads, but for off-road use it is better to choose forged wheels or stamped steel ones. Forged rims have a disadvantage, which is that due to their increased rigidity and strength, when receiving a serious blow or falling into a serious hole, the impact energy falls on the suspension elements.

Due to their light weight, alloy wheels are easier to accelerate and stop, the suspension is easier to operate, and there is better contact with the road surface. Such discs remove heat from the brakes, preventing them from overheating, thus increasing driving safety. Casting looks much more presentable than “stamps”, and as for the cost, they are, of course, more expensive, but still the price is reasonable. Alloy wheels of domestic production with a 15th radius cost approximately 2-3 thousand rubles. Imported casting will cost 3,500 rubles and more, the price can be several times more, depending on the coating of the disc and the complexity of the execution.

Forged wheels are the most expensive, despite the fact that the same materials are used in their production as in casting. But the higher price is due to their better characteristics obtained through the special technology used in production. A 15-inch disc, for example, weighs about 6-7 kg, and a cast one weighs 2-3 kg more. At the same time, forged wheels do not abound in a variety of shapes and complexity of patterns. Such discs made in Russia will cost 3-3.5 thousand rubles, while imported ones are much more expensive.

Alloy wheels for VAZ

15-inch wheels are often used on passenger cars, that is, in this segment they are standard in size. In addition, alloy wheels 16, 17, 19 R are used. As a rule, these are low-profile wheels. If desired, you can also install forged wheels, but due to the high cost, they are used much less often on such cars than light alloy and steel ones.

In the article, we reviewed different wheels, focusing in more detail on an option such as an alloy wheel, which is now increasingly being used.