High strength at room temperature does not necessarily occur when the material reaches high temperature. So, what exactly does heat tolerance mean? One is that the strength of the material remains low even at high temperature, the other is that the surface of the material is stable and does not change with the change of environment. Because with the increase of temperature, the common material can easily combine with oxygen in air, resulting in the change of size and coarsening the surface roughness.
Therefore, high speed tool steel belongs to heat resistant steel in a certain range. According to the stability of material surface.
stainless steel SUS304,SUS405,SUS403,SUS630 and so on belong to heat resistant steel. In fact, stainless steel standard heat-resistant steel already contains these materials. Heat-resistant steel SUH, has long been known as heat-resistant steel for the manufacture of automotive engine door SUH1,SUH3,SUH4 and so on.
They belong to martensite system and are typical representatives of hard cutting materials. Because they are hard, they have poor processability and are generally used below 700 ℃. SUH446 heat resistant Steel is a typical material of ferrite system. It is used to manufacture exhaust pipe of internal combustion engine with the aim of indicating stability.