The elongation of 304 stainless steel tube is small, the modulus of elasticity E is large, the hardening index is high, and the value of r-value of anisotropy index is very small (0.9-0.111 for 304 stainless steel and 1.3-2.0 for mild steel). 304 stainless steel tube from the yield to break the plastic deformation of the short period, in particular, its plastic strain ratio R greater than the weighted value.
304 stainless steel tube sheet drawing deep sometimes after the deformation in the deep drawing, sometimes in the deep drawing pieces from the die when the exit immediately; 304 stainless steel tube is sometimes in the deep deformation by shock or oscillation when the attack; When the deep drawing deformation after a period of storage or in the course of the attack. This article analyzes the causes of defects in 304 stainless steel tube sheet drawing, and puts forward the disposal methods.
Professional custom 304 stainless steel tube
1 Crack formation of the reason
Austenitic 304 stainless steel pipe cold work hardening index (304 stainless steel pipe 0.34). Austenitic 304 stainless steel tube is metastable, the deformation occurs when the phase transition, induced martensite phase. Martensite phase is brittle, and thus prone to cracking.
In the plastic deformation, with the increase of deformation, the higher the content of induced martensite phase, resulting in the greater the residual stress in the processing process is also easier to crack.
2 exterior scratches constitute the reason
304 stainless steel tube drawing parts of the surface is mainly due to scratch the surface of the workpiece and the relative movement of the mold surface, under the effect of a certain pressure, resulting in blank and mold part of the direct conflict, combined with the deformation of blank blanks and metal shavings In the mold surface, the workpiece surface scratches occur scratches.