摘要
为了对减速机齿轮的开裂原因进行研究并提出相应的改进措施,利用体式显微镜、扫描电镜、直读光谱仪和金相显微镜研究了齿轮的裂纹形貌、化学成分和微观组织。结果表明:齿轮的化学成分和硬度符合技术要求。齿轮的有效硬化层深度超过了技术要求,这会导致芯部受到较大的拉应力,是导致开裂的第1个原因。裂纹源位于断口芯部,并且有较多的O、Al、Ca、Na等元素组成的非金属夹杂物,这些夹杂物硬度较高,容易割裂材料的基体,受到外力时容易产生应力集中形成裂纹源,是导致开裂的第2个原因。针对上述开裂原因制定相关的改进措施,首先是不允许拼炉混装,其次是减少材料中的夹杂物。通过上述工艺改进,彻底解决了齿轮的早期开裂问题。
The cracking causes of gear in reducer were studied and the corresponding improvement measures were put forward.The crack morphology,chemical composition and microstructure of gears were analyzed by stereo microscope,SEM,OES and metallographic microscope.Results showed that the chemical composition and hardness of the gears met the technical requirements.The effective hardening depth of gears exceeded the technical requirements,leading to greater tensile stress in the center,which was the first cause of cracking.The crack source was located at the center of the fracture,and there were many non-metallic inclusions composed of O,Al,Ca,Na and other elements.These inclusions had high hardness and were easy to cut apart the matrix of the material.When subjected to external forces,stress concentration was easy to form the crack source,which was the second cause of cracking.In view of the above cracking reasons,relevant improvement measures were formulated.Firstly,it should not be allowed to mix and assemble the furnace,and secondly,it was necessary to reduce the inclusions in the material.Through the above process improvement,the problem of early cracking of gears had been thoroughly solved.
作者
周吉生
ZHOU Ji-sheng(College of Mechanical and Electrical Engineering,Henan Vocational University of Science and Technology,Zhoukou 466000,China)
出处
《材料保护》
CAS
CSCD
北大核心
2019年第11期166-169,共4页
Materials Protection
关键词
齿轮
硬化层深
夹杂物
应力集中
面扫描
gear
hardening depth
inclusion
stress concentration
surface scanning
