Fasteners are mechanical basic parts and are in great demand. Usually, bolts, screws, rivets, etc. are used to ensure safety or generally do not need to consider the influence of temperature in harsh environments or other dangerous working conditions. Commonly used materials are carbon steel, low alloy steel and non-ferrous metals. However, in certain occasions, fastener materials need to meet severe corrosion or high-strength conditions, and many stainless steels and ultra-high-strength stainless steels have emerged as the times require.

With the development of lightweight car bodies, aluminum is widely used in various positions of the car body. Die-cast aluminum is used in the front cabin, rear floor, A-pillar, CD-pillar and other areas, which can effectively realize the connection between the car body and other systems and meet good strength.