Application of die castings in automobiles

 In the die-casting market, the automotive industry occupies an extremely large share. According to relevant statistics, although the automotive industry occupies different shares due to different labor structures in different countries, the above ratio always ranks first. From the end of the 20th century to the beginning of the 21st century, the proportion of die castings in the automotive industry was about 48-80%. For example, Australia accounts for 80%, Japan accounts for 79%, Spain accounts for 65%, China accounts for 64.5 (including automobiles and motorcycles), Germany accounts for 61%, India accounts for 60%, Canada accounts for 49%, and the United States accounts for 48%. According to recent reports, this ratio in the United States has risen to about 75%. The automotive industry accounts for such a large share of die castings, which shows its important position in the die-casting industry. As far as China is concerned, this ratio has remained between 65%-75% in recent years (including vehicles, motorcycles and other means of transportation). As far as the automotive industry is concerned, this ratio has also increased significantly year by year.

 As for the number of die castings used per vehicle, it is reported (taking US data as an example) that in the early 1980s, the average weight of each vehicle was in the range of 1315-1542KG, and then decreased year by year. Taking the consumption of aluminum alloy castings per vehicle as an example, it is gradually increasing, with an average of 34kg per vehicle in 1980, 68KG in 1990, 1113kg in 2000, and 175KG in 2009. Aluminum alloy die castings account for more than 65% of all my castings.

 In addition, in addition to aluminum alloy die castings, zinc alloy, magnesium alloy and copper alloy die castings are also used in automobiles, so the number of die castings per vehicle is imaginable. The die-casting industry is closely related to the automotive industry.

 Looking back at the development history of the world's automobile industry, in the design and application process of various parts, great importance is attached to the use of die-casting parts, especially complex, large, and important parts, which are usually listed as the main research topics. This not only shows that the die-casting industry is irreplaceable in this respect, but also highlights that the development of the die-casting industry is largely based on the automotive industry. In other words, the die-casting industry is one of the important pillar industries of the automotive industry.

 Nowadays, people have higher and higher demands for automobiles, such as higher performance, low pollution, and low energy consumption. There are two ways to reduce energy consumption in automobiles: one is to improve the power system; the other is to reduce the weight of automobiles, that is, to quantify the number of automobiles. The most effective way to achieve lightweight is to manufacture auto parts with lightweight materials. In the 1970s, aluminum alloy castings (including various casting methods) were widely used in various countries to replace castings as important parts of automobiles.

 After that, with the gradual tightening of emission regulations in Europe and the United States, the requirements for energy conservation and emission reduction in the automobile manufacturing industry are getting higher and higher. At this time, finding materials that are lighter than aluminum alloy die castings to manufacture important auto parts has also become one of the research and development directions. It is worth mentioning that in the past 10 years, some leading manufacturers in the automotive industry have proposed the idea of using magnesium alloys to manufacture more parts, and have achieved certain results.

 It is worth mentioning that most of the high and new technologies for the development and innovation of the die-casting industry are developed around the high and new requirements of the automotive industry, including various required parts on various systems such as power, transmission, steering, body, frame, instruments, etc. Some of these parts are structural parts, load-bearing parts, safety parts and decorative parts.

 The most notable of these are: the use of aluminum alloy 390 complete die-casting technology to die-cast all-aluminum cylinder blocks, abandoning the original method of casting cast iron sleeves to enter aluminum alloy die-casting cylinder blocks; the use of ultra-low iron content new aluminum alloy SF36 to manufacture automobile body frame connectors, changing the new field of titanium alloy die-casting technology. Aluminum alloy die-casting diesel engine housings have been published in recent years, which is a prelude to die-casting entering the diesel engine field.

Some results have been achieved in reducing the weight of automobiles with magnesium alloy die castings, forming some current research hotspots and main research directions. For example, magnesium alloy die castings are used in power systems and transmission systems, which further expands the application of magnesium alloy die castings in the automotive industry. However, it should be pointed out that for magnesium alloy die castings, when considering replacing other alloys and materials with magnesium alloy to produce parts, it is necessary to first understand the characteristics of this material, rather than acting blindly. In addition, in the production process, attention should be paid to safety, environmental protection and other issues.

Another example is the development of various technical methods to solve porosity. These methods include vacuum die casting, ACRAD die casting, oxygen oxidation die casting, uniform acceleration slow injection technology, local pressurization technology, etc. There are also squeeze casting and semi-solid forming technology. These undoubtedly inject new vitality into the die-casting process, making it possible to obtain die-casting parts with high strength, high density, heat treatment, weldability and other characteristics.