热处理对形变强化非调制钢力学性能的影响机理学案.doc

南 京 工 程 学 院 毕业设计说明书(论文) 作 者： 张再磊 学 号： 240100535 学院（系、部）： 康尼学院 专 业： 材料科学与工程 题 目： 热处理对形变强化非调质钢性能 影响机理研究 指导者： 评阅者： 2014 年毕业设计说明书（论文）中文摘要 热处理对形变强化非调质钢性能影响机理研究 本试验所用材料为拉拔态的MFT8非调质钢，研究了不同时效工艺对非调质钢力学性能的影响。通过金相显微镜观察试样时效处理前后的显微组织；通过显微硬度计测量时效处理前后试样的硬度变化；通过拉伸试验检测量时效前后试样的抗拉强度、断后伸长率；通过纳米压痕仪测量时效前后试样的纳米硬度、弹性模量；通过扫描电镜观察拉伸后试样的断口形貌。实验结果表明：经过低温时效处理的试样的强度、硬度增强。随着时效温度的升高，强度、塑性不断增强且在300℃、保温2h的试样具有最佳的强度和塑性配合，其原因可能是低温时效处理过的试样组织中有第二相颗粒析出。 关键词：非调质钢；时效；硬度；弹性模量 毕业设计说明书（论文）外文摘要 Title The Influence of Heat Treatment on Mechanism and Properties of Deformation Strengthening Microalloyed Steel Abstract: The raw material was drawing state microalloyed steel MFT8. The effect of various aging processes on the mechanical properties of microalloyed steel was investigated. The microstructure of specimens before and after aging treatment was observed by microscope. The microhardness of samples before and after aging treatment was measured. The tensile properties of the samples before and after aging treatment were measured by tensile test. The nanomechanical properties of the samples before and after aging treatment were tested by nano indentation. The facture morphologies were observed and analyzed by scanning electron microscopic (SEM). The experimental results show that the strength and plasticity of the samples after aging treatment at low temperatures are reinforced. The strength and plasticity increases along with the increasing of heating temperature. The samples aged at 300℃ for two hours have the best combination of strength and plasticity, owing to the second phase strengthening by particles precipitated in ferrite grains. Keywords: Microalloyed Steel; Aging treatment; Hardness; Modulus of elasticity 目 录 前 言 1 第一章 绪论 2 1.1 非调质钢 2 1.2 非调质钢的发展 2 1.2.1 国外非调