Screws as a common fastener, carbon steel material is also a common screw material, of course, carbon steel is also divided into different carbon steel screw materials, according to different materials carbon steel screws after heat treatment, the grade is also different, according to a detailed understanding, share the following types of carbon steel screw materials after heat treatment can achieve what level of important information.
1010/1018/1022 Carbon steel grade 1010,1018,1022 material of low carbon steel screws can only reach 4.8 or below without hardening. Different grades of wire have different levels of strength. It should be noted that: as a low carbon steel material below 1018, after the heat treatment processing process, the strength level of the screw can reach 6.8. However, heat treatment can only improve the surface hardness of low carbon steel screws, and there is almost no change in the core. Therefore, the strength level of low carbon steel generally refers to the Vickers hardness of low carbon steel screws (refers to the hardness of the screw surface, which is a routine test). 10B21 Carbon steel screws of 10B21 material can reach 8.8 or above after hardening treatment, and chromium hardness (HRC) can be detected (refers to the detection of surface hardness and core hardness of carbon steel screws). CM435 carbon steel steel screws of CM435 material can reach class 10.9 and 12.9 after hardening, and can also detect (HRC) surface hardness and core hardness.
45K carbon steel material is a material of tempering, which refers to the tempering treatment of 45K wire (double heat treatment of quenching and high temperature tempering). The plasticity, toughness, strength and other properties of the steel are improved, which effectively avoids the deformation of the screws in the late heat treatment process. Preheat production during production and increase the intermediate production process, so that 45K carbon steel screws can reach 8.8 grade after production. In addition to the requirements of the above carbon steel materials are often hardened, stainless iron 410, 430 and 7 series of alloy aluminum can also be hardened, without considering the production cost of screws, boron, carbon, nitrogen and other aspects of the three elements of synthetizing, etc. Almost all metal materials can be hardened, but not only the cost of the problem, more is the complexity of the operation, almost no manufacturers will do this kind of thing.
