摘要
冷焊技术是一种新型金属零件表面修复技术,具有精密、经济、便捷等优点,已应用在发动机再制造等领域。利用冷焊技术对发动机缸体材料HT250表面缺陷进行修复,采用金相显微镜、扫描电镜、显微硬度计和拉伸试验机等设备对修复区域的微观组织、硬度和结合强度进行测试分析,同时揭示不同冷焊工艺参数对修复层性能的影响。研究结果表明:基体与修复层结合良好,无孔隙和裂纹,熔合区存在元素扩散,说明修复层与基体间是微区冶金结合;修复层硬度低于基体硬度,便于后续加工处理,热影响区较小;冷焊修复技术能提高修复对象的抗拉强度。同时,热影响区宽度和硬度随冷焊时间和能量工艺参数的增大而增大;抗拉强度的变化随冷焊时间和能量工艺参数的增大先有减小趋势,后逐渐增大。
Cold-welding technology is a new type of metal surface repair technique with advantages of precision, economy and convenience, and has been widely used in engine remanufacturing and other fields. The surface defects of HT250 material used in engine cylinder are repaired by cold-welding technology, then the metallographic microscope, scanning electron microscope, microscopic hardness meter and tensile testing machine are used to analyze microstructure, hardness and bonding strength of repaired region. Meanwhile, the impacts on repaired layer of different process parameters are revealed. Analysis results show that base and repaired layer combine well without pores and cracks, and element diffusion exists in the fusion interface, which illustrates that the relationship between repaired layer and base is metallurgical bonding. The hardness of repaired layer is lower than that of base, which is beneficial to subsequent processing. The width of heat affected zone （HAZ） is relatively narrow. Cold-welding repair technique can improve tensile strength of repaired object. After analyses, the following trends can be obtained that width and hardness of HAZ increase with the increase in time and energy parameters of cold-welding, while tensile strength firstly decreases and then increases.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2013年第7期101-105,共5页
Journal of Mechanical Engineering
基金
国家重点基础研究发展计划(973计划
2011CB013403)
山东大学自主创新基金(2012ZD010)
泰山学者建设工程和潍柴动力(潍坊)再制造有限公司资助项目
关键词
冷焊
再制造
发动机
工艺参数
Cold-welding Remanufacturing Engine Parameters
