在Gleeble-3800热模拟试验机上进行了一种新型Mn-N合金化双相不锈钢的拉伸变形实验，获得了不同固溶温度下(1000~1200 ℃)不锈钢的力学性能及加工硬化规律。利用OM、SEM和EBSD等手段研究了固溶温度对钢的形变亚结构及断裂特征的影响，探讨了固溶温度影响加工硬化的机理。结果表明，随着固溶温度的升高，Mn-N合金化双相不锈钢屈服强度与抗拉强度均逐渐降低，而延伸率(均匀延伸率和断裂延伸率)则先升高后降低。其中，1100 ℃固溶时不锈钢的塑性最佳，均匀延伸率可达46.7%，且综合力学性能优异，强塑积达44.6 GPa·%。不同固溶温度下，不锈钢的加工硬化率随应变的增加均表现为开始时迅速下降，经再次升高后再下降的“三阶段”特征，但随着固溶温度的升高，加工硬化率升高的趋势减弱。Mn-N合金化双相不锈钢中奥氏体相发生了形变诱导马氏体相变，主要表现为γ→ε→α′和γ→α′ 2种演化机制，从而形成TRIP效应，使得加工硬化率升高、塑性增加，但较高的固溶温度会使马氏体转变受到抑制。不同固溶温度下，铁素体与形变诱导马氏体均表现出解理断裂特征，而残余奥氏体则主要为韧性断裂。经计算，随着固溶温度增加(1000~1200 ℃)，奥氏体相的M_d30值从81 ℃降到38 ℃，即奥氏体稳定性增加，减弱了TRIP效应，进而导致不锈钢加工硬化和增塑效果降低。

Advanced duplex stainless steels (DSSs) in which Ni is mostly or completely replaced by Mn and N have been developed in recent years. Such Mn-N bearing DSSs can readily achieve exceptional room-temperature tensile properties through the transformation-induced plasticity (TRIP) effect of metastable austenite. During the processing of DSSs, solution treatment is a critical step that tailors the phase fraction and the overall properties. In particular, the phase chemistry can change due to different element partitioning between two constituents, resulting in a different TRIP kinetics, when DSS is solution treated at different temperature. In this work, the effect of solution temperature on tensile deformation behavior of a new Mn-N bearing DSS was studied. The mechanical properties and work-hardening characteristic of the steels solution treated at different solution temperature (1000~1200 ℃) were investigated by thermal modeling test, and the effects of solution temperature on the deformation substructure and fracture characteristics were analyzed by OM, SEM and EBSD. The results show that as the solution temperature increases, the yield strength and tensile strength of the steels decrease, while the elongation (uniform elongation and total elongation) increases firstly and then decreases. The steel solution treated at 1100 ℃ shows the optimum uniform elongation of 46.7%, and a better combination of ultimate tensile strength and ductility of approximately 44.6 GPa·%. The work-hardening rate of the steel shows a three-stage characteristic, namely it declines firstly and then increases and subsequently declines again as the strain increases. However, the increasing extent of the work-hardening rate decreases as the solution temperature increases. The strain-induced martensitic transformation (SIMT) of metastable austenite which causes the TRIP effect has two evolution mechanisms of γ→ε→α' and γ→α'. But SIMT can be suppressed when the solution temperature increases. The fracture surfaces of specimens solution treated at different temperatures show a quasi-cleavage mode, in which both ferrite and strain-induced martensite exhibit cleavage fracture while the residual austenite displays a dimple-mode fracture. Furthermore, the M_d30 which can characterize the stability of metastable austenite was calculated, which decreases from 81 ℃ to 38 ℃ as the solution temperature increases from 1000 ℃ to 1200 ℃, indicating that the TRIP effect gets weakening at a higher solution temperature, and the work-hardening and plasticity therefore decrease.