What are the characteristics of high temperature resistant stainless steel welded pipe compared with

Compared with carbon steel, 　　high temperature stainless steel welded pipe has a slightly higher density than ferrite and martensitic stainless steel, and slightly lower than high temperature resistant stainless steel; resistivity is carbon steel, ferrite type, martensite type and austenitic The order of the stainless steel is increasing; the order of the coefficient of linear expansion is similar, the austenitic stainless steel is the highest and the carbon steel is the smallest; the carbon steel, ferritic and martensitic stainless steel are magnetic, and the austenitic stainless steel is non-magnetic, but its When cold work hardening forms a phase transformation, it will generate magnetism, and the martensite structure can be removed by heat treatment to restore its non-magnetic properties.


　　Compared with carbon steel, austenitic stainless steel welded pipe has the following characteristics:


　　1) High electricity rate, about 5 times that of carbon steel.


　　2) The large coefficient of linear expansion is 40% larger than that of carbon steel, and as the temperature increases, the value of the coefficient of linear expansion increases accordingly.


　　3) Low thermal conductivity, about 1/3 of carbon steel.


　　Mechanical properties of austenitic stainless steel


　　Regardless of high-temperature resistant stainless steel welded pipe sheets or heat-resistant steel sheets, austenitic steel sheets have the best overall performance, and have sufficient strength, excellent plasticity and low hardness, which is why they are widely used. One. Austenitic stainless steels are similar to most other metal materials. Their tensile strength, yield strength and hardness increase with decreasing temperature; plasticity decreases with decreasing temperature. Its tensile strength is relatively uniform in the temperature range of 1580 degrees. More importantly, as the temperature decreases, the impact toughness decreases slowly and there is no brittle transition temperature. Therefore, stainless steel maintains sufficient plasticity and toughness at low temperatures.