船用凸轮轴的连续中频感应淬火

本文记述了我厂通过革新的感应器设计及工艺过程优化，成功地在国产数控机床和中频电源上实现了船用凸轮轴9个3组不同尺寸的凸轮的连续中频感应淬火生产，通过改进，产品质量的稳定性和高生产效率同时得到了兼顾。     

带偏心轮凸轮轴的感应加热淬火

介绍了上海柴油机股份有限公司从德国EFD公司引进的凸轮轴感应淬火机床的结构、电源系统、控制系统和循环冷却装置，以及带偏心轮凸轮轴感应淬火工艺的实施和工艺参数。     

凸轮轴感应加热淬火设备和工艺

汽油机凸轮轴感应加热表面淬火有两种工艺方法,一种是逐个凸轮加热冷却,另一种是全部凸轮同时加热冷却。目前国内生产厂家都采用前一种,一方面由于受到设备条件的限制,另一方面这种工艺方法更适合于多品种小批量的生产方式。我厂利用卧式淬火机床配国内新开发的大功率...     

50Mn钢凸轮轴的中频感应淬火

凸轮轴是柴油机的重要传动件之一,要求根据所采用的材料进行渗碳淬火或表面淬火,以提高其表面硬度和耐磨性。50Mn钢凸轮轴采用BVH-1000双工位中频淬火机床、仿形感应器和专用夹具等设备,以及10％～15％AQ251聚合物水溶液进行感应淬火。结果,凸轮轴的表面硬度、硬化层深度分布和显微组织均达到了要求,生产成本明显低于进行渗碳淬火的20Cr钢凸轮轴。     

凸轮轴超音频淬火工艺的改进

一种摩托车发动机用凸轮轴,材料为QT600-3球墨铸铁,要求其工作面具有足够的硬度和耐磨性。采用局部超音频感应淬火能达到凸轮轴的性能要求,但凸轮部位易过热、烧熔或开裂。改进淬火操作方法后,这些问题得到了解决。     

在凸轮轴上测量凸轮升程中修正偏心影响的计算方法

本文对凸轮轴上的凸轮升程的测量基准和设计基准不重合问题进行了探讨，提出了凸轮轴上凸轮升程的测量方法及相应的修正计算公式。     

制动凸轮轴轴颈淬火感应器改进与应用

分析制动凸轮轴轴颈感应淬火特点,通过对原淬火感应器的改进,设计出新的分离型可移动式并联矩形感应器,提高了感应器的通用性及生产效率。     

凸轮轴凸轮的单面屏蔽淬火及其动态定位法

凸轮轴是发动机配气机构中的主要零件,它与气阀挺杆组成一对摩擦副,如图１所示。工作时除承受一定的弯曲和扭转载荷外,主要是凸轮部分承受变化的挤压力以及挺杆的摩擦力［１］,工作时要求有很高的耐磨性,因此要求有很高的硬度。图１凸轮轴示意图１．轴颈２．凸轮我厂...     

船用柴油机凸轮轴中频淬火工艺数值模拟分析

针对凸轮轴零件中的凸轮部位感应淬火工艺淬硬层不均匀、局部残余应力过大的问题,采用SYSWELD软件中的热处理模块,建立凸轮感应淬火工艺有限元模型,基于可变换热系数及奥氏体动力学理论,对GCr15凸轮轴中频感应淬火过程进行仿真分析,获得淬硬层厚度、硬度以及凸轮残余应力场分布规律。结果表明,在加热功率为110~120 kW,频率为5 600 Hz,加热时间为6 s时,过渡轮廓面淬硬层最薄处为1.34 mm,表面硬度均达到700 HV以上,桃尖表面残余压应力为-50 Pa,过渡轮廓面达到-350 MPa。     

齿轮单频及同步双频感应淬火工艺的比较研究

根据各类齿轮不同齿轮模数、形状及其淬硬层深度、硬度、显微组织,热处理畸变要求的应用范围,比较高频、中频感应淬火、双频、SDF 同步双频感应淬火工艺的优缺点及其应用范围。     

Effects of induction hardening and prior cold work on a microalloyed medium carbon steel

The torsional strength and microstructural response to induction hardening of a 10V45 steel with prior cold work was evaluated. The vanadium-microalloyed 1045 (10V45) steel was characterized in three conditions: as-hot-rolled, 18% cold-reduced, and 29% cold-reduced. Two of these evaluations, 10V45 as-hot-rolled and 10V45-18%, were subjected to stationary and progressive induction hardening to three nominal case depths: 2, 4, and 6 mm. All specimens were subsequently furnace tempered at 190 °C for 1 h. The martensitic case microstructures contained residual lamellar carbides due to incomplete dissolution of the pearlitic carbides in the prior microstructure. Torsional overload strength, as measured by maximum torque capacity, is greatly increased by increasing case depth, and to a lesser extent by increasing prior cold work level. Maximum torque capacity ranges from 2520 to 3170 N · m, depending upon induction hardening processing. Changing induction hardening processing from stationary (single-shot) to progressive (scan) had little effect on torque capacity. This paper was originally presented at the 17th ASM Heat Treating Society Conference, which included the 1st International Induction Heat Treating Symposium, 1997.     

防止零件表面尖角部位感应淬火开裂方法

为了防止零件表面尖角部位在感应淬火过程中发生开裂,设计了一种装置,可以将零件表面尖角部位完全遮盖。该装置同时可以避免因感应器与零件接触而造成短路,从而避免零件被电流击伤。结果表明：使用该防开裂装置及方法,不仅可以有效避免零件表面尖角部位在感应淬火过程中发生开裂,而且可以避免零件被电流击伤。     

基于PLC与HMI的感应淬火机床控制系统的设计

针对回转支承整体淬火机床功能单一、控制系统开放性差、难以实现数据管理等问题,设计了以PLC为控制核心、HMI触摸屏为人机交互界面的淬火机床全自动控制系统。实现了整体淬火工序的时序与逻辑控制;通过触摸屏监测加工的动态过程,可对零件加工参数进行实时存取操作;系统中功率和淬冷时间等关键参数可依据用户的工艺需求设定,不仅解决了数据管理和系统开放性不足的问题,还提高了淬火效率和淬火稳定性,实现了整体淬火的自动化控制。     

An analysis of induction hardening of ferritic ductile iron

Achievements of the induction hardening of ferritic ductile iron were investigated. Ductile iron is not advisable for use in induction hardening because of the small carbon content in the metal matrix of ferritic ductile iron. The carbon content in the metal matrix of ductile iron can be increased by additional preparation of metal matrix before final induction heat hardening. Wear resistance of the induction hardened ferritic ductile iron can increase as result of increased carbon content of the metal matrix and higher hardness after induction hardening. Some heat pretreatments for metal matrix preparation were applied before the induction hardening of ferritic ductile iron. The process parameters of the induction hardening heat pretreatment were analyzed and optimized. According to recommended elemental composition of ferritic ductile iron and required mechanical properties, the process parameters of the investigated induction heat pretreatment were optimized. The efficiency of pretreatment processes of induction hardening was analyzed. Applicability and manufacture ability of engineering components by proposed heat pretreatments were investigated. The limitations of the investigated heat pretreatment applications were estimated by the comparison of mechanical properties of heat-treated specimens.     

FEM modeling of induction hardening processes in steel

A modeling system for analyzing the integrated induction hardening processes was developed based on a general-purpose finite element program, with the capability to analyze the whole process from electromagnetic-induced thermal heating to final hardening. A coupled electromagnetic-thermal model was applied to study the induction heating process, which includes consideration of nonlinear material characteristics on temperature. Also, arrangement of AC current density distribution was conducted to simulate practical induction coil structure and magnetic concentrator effects to achieve desired heating patterns for later quenching and hardening analysis. Quenching analysis can provide cooling curve at any location in a heat-treated workpiece based on heat transfer principles. In hardening analysis, phase transformation was studied and an algorithm was developed to determine volumetric content of micro-structural constituents formed from austenitized phase in quenching process, based on analysis of the interaction between cooling curve and material time-temperature-transformation (TTT) diagram. Finally, hardness value was converted from martensite content based on a developed formulation. Validation was preliminary conducted based on comparison of hardening pattern of induction hardening of an automotive spindle with complex surface.     

表面感应淬火对45钢滚动磨损特性的影响

针对传统热处理后45钢耐磨性较低的缺点,研究了正火 表面感应淬火热处理后45钢相对ZG31Mn2Si摩擦副的滚动磨损特性和磨损机理.测试了试验载荷、材料硬度与磨损失重的关系,采用扫描电镜分析了感应淬火热处理后不同硬度45钢的磨损形貌及变化规律.结果表明:当载荷恒定,磨料硬度Ha大于被磨材料45钢硬度Hm时,45钢随着感应淬火后自身硬度的提高,耐磨性明显提高,为硬磨料磨损;Ha＜Hm时,随着材料硬度的提高,磨损量变化很小,为软磨料磨损;其滚动磨损机理随着表面感应淬火后硬度的升高由塑变磨损转变为犁沟磨损.     

基于ANSYS的多点式中频感应淬火温度场有限元模拟

研究了用多个淬火感应器对半径较大的回转体表面进行中频感应淬火的作用机理,针对较大半径的回转体表面的多点式感应淬火工艺进行参数设计,建立了多点式感应淬火过程的电磁场和温度场的非线性偏微分方程组。利用有限元分析ANSYS软件来模拟多点式中频感应加热过程,其中对激励电流用表格法加载来近似地替代实际旋转工件周期性的感应淬火,从而得到了工件温度场随时间的变化规律以及最终工件的温度场分布。结果表明,多点式中频感应淬火改善了较大半径的回转体的凹槽表面淬火过程,可以达到对感应淬火工件淬硬层的要求,解决了由于不同时感应淬火所导致的软带问题。     

新型非调质钢曲轴中频感应圆角淬火的质量控制

从人员、设备、感应器、淬火前机加工尺寸、淬火硬度和淬火介质等几方面,阐述了新型非调质钢曲轴中频感应圆角淬火质量控制方法.