Characteristics of 100Cr6 bearing steel after thixoforming process performed with prototype device

来源 :Transactions of Nonferrous Metals Society of China | 被引量 : 0次 | 上传用户:haiyan100
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
A device based on a high pressure die-casting(HPDC) machine was constructed,with a capacity to produce thixo-casts from steel.After inductive heating to the required semi-solid temperature range,the samples were transported in a protective argon atmosphere to a cylinder of modified HPDC and injected into a pre-heated die.Bearing steel 100Cr6(after forging) was used as the feedstock material.The metallographic analysis of the steel showed a homogenous structure within a whole volume characterized by a grain size between 2 μm and 8 μm.Differential scanning calorimetry(DSC) analysis allowed to estimate the process temperature for thixoforming at 1 390 ?C which was attributed to about 45% of a liquid phase.With such technological parameters after the semi-solid processing the microstructure consisted of globular grains of size from 15 μm to 40 μm.The microstructure of globules indicated predominant presence of martensite(about 76% volume fraction) with residual austenite between plates.X-ray analysis confirmed that the thixo-cast samples contain mainly martensite and residual austenite.The hardness of the initial forged sample was HRC 27 and after the thixoforming process it was HRC 60,which confirms the presence of martensite and carbides.The thixo-casts were subjected to low tempering,at temperature of 150 °C for a period of 2 h,in order to remove stresses created during the process of thixoforming and to increase plasticity.The hardness after tempering was HRC 62.3.Additionally,in order to identify phases present in the thixo-casts,transmission electron microscopy(TEM) was carried out. A device based on a high pressure die-casting (HPDC) machine was constructed, with a capacity to produce thixo-casts from steel. After inductive heating to the required semi-solid temperature range, the samples were transported in a protective argon atmosphere to a cylinder of modified HPDC and injected into a pre-heated die.Bearing steel 100Cr6 (after forging) was used as the feedstock material. metallographic analysis of the steel showed a homogenous structure within a whole volume characterized by a grain size between 2 μm and 8 μm. Differential scanning calorimetry (DSC) analysis allowed to estimate the process temperature for thixoforming at 1 390 ° C which was attributed to about 45% of a liquid phase. How such technological parameters after the semi-solid processing the microscopic consisted of Globular grains of size from 15 μm to 40 μm. The microstructure of globules indicates predominant presence of martensite (about 76% volume fraction) with residual austenite between plates . X-ray analysis confirmed that the thixo-cast samples contain mainly martensite and residual austenite. The hardness of the initial forged sample was HRC 27 and after the thixoforming process it was HRC 60, which confirms the presence of martensite and carbides. Thixo -casts were subjected to low tempering, at a temperature of 150 ° C for a period of 2 h, in order to remove stresses created by the process of thixoforming and to increase plasticity. hardness after tempering was HRC 62.3. Additionally, in order to identify phases present in the thixo-casts, transmission electron microscopy (TEM) was carried out.
其他文献
苏州大学附属第一医院蒋文平教授,早年毕业于大连医学院并赴匈牙利留学,获博士学位回国。先后就职于中国医学科学院阜外医院、苏州大学第一附属医院。担任过心内科、内科、医
引入了粉尘防爆的定义及成因,对防爆型卸船机的防爆区域划分及关键部件的防爆措施做以简要介绍。 The definition and cause of dust explosion protection are introduced.
潍坊港与“一带一路”战略重点规划发展的其他大港相比,存在自然条件差、信息化建设滞后、产业集聚度不高等竞争劣势,周边中小港口的迅速发展也对潍坊港形成了竞争压力。潍坊
吉林省公路学会于6月17日至18日在吉林市召开了换届会议,即七届一次理事会议。七届理事会共由57名理事组成,是经各会员单位推荐,通过选举产生。新当选的理事、各地区学会和
吉林省公路学会科普教育工作委员会会议于8月2日至3月在集安市召开。该委员会主任委员、省交通学校校长苗庆贵及来自吉林、四平、通化、松原等地区和省交通科研所、省公路设
“第三终端”,作为一个新的概念,正不断地在医药界内人士的口中说出、耳边回响,但实际上“装在这个新瓶里的却是旧酒”。需要强调的一点是,言其“新瓶装旧酒”只是指“第三终
期刊
刀””””孙””冲介”认刀冲竹介”))))))劝”””协”冲分””冲”””协冲))))””介”钱”冲穷”冲”””钱刀”协冲协))”冲冲”垅””钱刃”冲””冲))))冲冲))))))))
1996年10月8日——11日,全国公路学会系统学术刊物经验交流会在长春市召开。参加会议的有:中国公路学会主办的《中国公路》、北京市公路学会主办的《北京公路》、东北地区公
大跨径预应力混凝土连续梁桥应用越来越多,本文介绍设计中应注意的几个问题,对于提高设计水平有很大的帮助。 The application of large span prestressed concrete continu