00Cr22Ni5Mo3N双相不锈钢的低温超塑性研究

通过恒温热拉伸的方法研究了太钢生产的00Cr22Ni5Mo3N双相不锈钢的超塑性行为,其中重点研究了该材料的低温超塑性。在850℃的超塑性变形过程中,当初始应变速率为2.5×10~(-3)s~(-1)时,获得了500％的最大延伸率。在800℃～900℃的低温区,δ铁素体分解成γ和σ相,从而导致最终的δ/γ和γ/σ组织。微观组织分析表明:该双相不锈钢超塑性变形的机理是形变诱导相变、晶界的滑移和晶粒的转动。

Study on superplasticity of 00Cr22Ni5Mo3N duplex stainless steel in lower temperatures

Superplastic behavior of a micro-duplex stainless steel produced by Taiyuan Iron &. Steel Group has been studied by means of isothermal hot tensile test. More attention was pay on the superplasticity in lower temperatures. At 850 ℃ , the best elongation 500% was achieved for an initial strain rate of 2. 5 × 10-3 s-1. At lower temperatures between 800℃ and 900℃ , a phase was formed through eutectoid decomposition of the 8, resulting finally in the stable equiaxed micro - duplex structures with γ/σ and δ/γ, respectively. Microstructural studies suggest that the superplastic process occurs mainly by the strain induced dynamic transformation and grain boundary sliding and grain switching mechanism.