The process performance and permeability of stainless steel strip at ultra-low temperature are very small, so it is also called non-magnetic raw material. Steels with stable austenite structure, such as 0 CR 20 Ni 10 and 0 CR 25 Ni 20, will not be magnetic even if they are processed with large deformation of more than 80%. In addition, high carbon steel, high nitrogen and high manganese austenitic stainless steel, such as 1cr17mn6nisn, 1Cr18Mn8Ni5N series products and their high manganese austenitic stainless steel, can be produced under the production and processing standards of large reduction ε The phase changes and thus remains non-magnetic< br>
At high temperatures above the Curie point, even strong magnet materials will lose magnetism. However, some austenitic stainless steels, such as 1cr17ni7 and 0Cr18Ni9, have a metastable austenite mechanism. Therefore, austenite will change when carrying out large reduction and cold drawing or ultra-low temperature production and processing. They will have their own magnetism and permeability will also be improved< br>
The vertical elastic die of metallographic stainless steel under indoor temperature of stainless steel strip is 200kn/mm2, and the vertical elastic die of austenitic stainless steel is 193kn/mm2, slightly low carbon steel. With the increase of temperature, the vertical elastic die decreases, the Poisson's ratio increases, and the horizontal elastic die (stiffness) decreases significantly. The vertical elastic die will do harm to the combination of cold work hardening and mechanism. The relative density of stainless steel strip. The relative density of metallographic stainless steel with high chromium content is small. The density of austenitic stainless steel with high nickel content and high manganese content is large. The relative density decreases due to the increase of quality interval at high temperature< br>
Process performance of stainless steel strip at ultra-low temperature
(1) Heat transfer coefficient the size of heat transfer coefficient of various stainless steels at very low temperature is slightly different, but generally speaking, the heat transfer coefficient is about 1/50 of that at indoor temperature. At ultra-low temperature, the heat transfer coefficient increases with the increase of magnetic flux (magnetic flux density)< br>
(2) Specific heat capacity at very low temperatures, there are some differences in the specific heat capacity of various stainless steels. The specific heat capacity is greatly affected by temperature. The specific heat capacity at 4K can be reduced to less than 1/100 of the specific heat capacity at indoor temperature< br>
(3) For austenitic stainless steel, the size of shrinkage (relative to 273k) below 80K is slightly different. The composition of nickel is harmful to shrinkage< br>
(4) The difference of resistance size among models increases at very low temperature. Aluminum alloy elements do great harm to the size of resistance< br>