东北大学学报(自然科学版) ›› 2013, Vol. 34 ›› Issue (10): 1420-1424.DOI: -

• 材料与冶金 • 上一篇    下一篇

轧件内部裂纹的模拟实验方法与愈合行为

刘相华1,艾峥嵘1,喻海良2,3   

  1. (1.东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110819;2.卧龙岗大学机械、材料、机电工程学院,澳大利亚新南威尔士州2500;3.沈阳大学机械工程学院,辽宁沈阳110044)
  • 收稿日期:2013-04-23 修回日期:2013-04-23 出版日期:2013-10-15 发布日期:2013-05-24
  • 通讯作者: 刘相华
  • 作者简介:刘相华(1953-),男,黑龙江双鸭山人,东北大学教授,博士生导师;喻海良(1980-),男,湖南长沙人,卧龙岗大学访问学者,沈阳大学教授.
  • 基金资助:
    国家自然科学基金资助项目(51105071,51204050).

Experiment Method to Simulate Internal Cracks and Its Healing Behavior of Rolled Pieces

LIU Xianghua1, AI Zhengrong1, YU Hailiang2,3   

  1. 1. State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819, China; 2. School of Mechanical, Materials & Mechatronic Engineering, University of Wollongong, NSW 2500, Australia; 3. School of Mechanical Engineering, Shenyang University, Shenyang 110044, China.
  • Received:2013-04-23 Revised:2013-04-23 Online:2013-10-15 Published:2013-05-24
  • Contact: AI Zhengrong
  • About author:-
  • Supported by:
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摘要: 提出一种预置轧件内部裂纹的模拟实验新方法,即钻孔填充法,将其用于普碳钢中厚板内部裂纹的预置,并对其愈合行为进行轧制实验研究.研究了位于轧件中心、厚度方向三分之一处等位置的裂纹愈合情况.实验结果表明,压下率达到50%以上、开轧温度在1100℃时,内部裂纹可完全愈合;且位于轧件厚向中心位置裂纹的愈合程度好于其他位置,采用缓冷方式时裂纹的愈合程度好于空冷.对轧制过程中裂纹愈合的机理进行了分析,认为在轧制变形条件下,压应力状态为裂纹愈合提供了静力学条件,塑性变形过程中大量原子的定向运动,为裂纹愈合提供了物质补给条件,裂纹两侧的金属原子更容易找到新的平衡位置,形成统一的晶格点阵,从而实现裂纹愈合.

关键词: 内部裂纹, 裂纹愈合, 轧制, 预置裂纹, 普碳钢

Abstract: A new experiment method called hole filling method was proposed to simulate the internal cracks inside rolled pieces. The healing behavior of internal cracks in a mild steel plate during rolling was studied by presetting internal cracks in a sample. The crack healing tests in the center and 1/3 height of the plate were carried out. The results showed that internal cracks heal completely at the reduction of more than 50%and the rolling temperature 1100℃. The crack in the center of the plate healed better than that at other places, and cooling slowly after rolling was good for healing. The mechanism of crack healing in the rolling processes was analyzed. During the rolling deformation, the compressive stress state provides the static condition for crack healing. When the plastic deformation went on, as the huge atoms move towards one direction, which provided the material supply condition for crack healing, the atoms on two sides of the crack are easy to find a stable location to form a crystal lattice, then the crack heal.

Key words: internal crack, crack healing, rolling, presetting crack, plain carbon steel

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