The formability of cold rolled stainless steel sheet was studied by measuring its R-value, strain-hardening exponent Limit Drawing Ratio(LDR), Forming Limit Diagram (FLD), texture and tensile property. The relationship between the R-value and the mechanical properties on crystal structure was investigated by a method of regression-analysis with the results, R-value==0.798+0.244 (TS/YS)-10.225 n+0.0655 EL in BCC structure and R-Value= 1.165-6.86 × 10^(-3) (TS/YS) -1.11 n+5.9828 ×10^(-3) EL in FCC structure. The characteristic value of FLD was little affected by the thickness of stainless steel sheet. However, the Characteristic vague of FLD of austenitic stainless steel was higher than that of the ferritic stainless steel, because it had a higher strain-hardening exponent The high R-value increased the uniform plastic strain of the drawing region but reduced the stretching region. |
|