大型板料成形件压形—淬火模的设计

１工艺分析１．１工艺特点大型板料在压形—淬火模上完成的成形、淬火工艺，实际上就是将经过加热的板料在模具上成形后，再利用模具中的喷水装置对工件进行喷水淬火，使工件的成形和淬火两道工序一次完成。这样可保证工件淬火时不发生变形或只有少量的变形，从而简化校形...     

模具钢淬透性及淬火变形分析研究

通过对影响模具钢淬透性因素和淬火变形的机理分析研究,指出模具钢的淬透性及淬火热处理变形的影响因素是十分复杂的问题。在制定淬火热处理工艺时,应充分考虑工件的形状、钢中的碳含量,根据工件所要求的力学性能,合理选择淬火方法及冷却介质,防止变形及开裂,提高产品质量。     

模具钢淬透性及淬火变形分析研究

通过对影响模具钢淬透性因素和淬火变形的机理分析研究,指出了模具钢的淬透性及淬火热处理变形的影响因素,在制定淬火热处理工艺时,应充分考虑工件的形状、钢中的碳含量,根据工件所要求的力学性能,合理选择淬火方法及冷却介质,防止变形及开裂,以提高产品质量。     

液态淬火介质的两个共性的缺点及对策

适用范围有限和工件淬火变形大是液态淬火剂的两个带有共性的缺点,提出了克服第一个缺点即扩大液态淬火剂的应用范围的8种技术措施,指出,工件的淬火变形量除淬火介质的冷却速度外,还与其特性温度有关,应选用特性温度稳定的介质淬火。     

不同浓度氯化钙溶液对碳素工具钢淬火质量的影响

对碳素工具钢采用不同浓度的氯化钙水溶液进行淬火。结果表明，饱和氯化钙水溶液冷却可在保证工件淬硬性的前提下，减少淬火工件的变形、开裂，提高碳素工具钢的淬火质量。     

单容器双液淬火法的探讨

介绍了一种新的淬火方法—单容器双液淬火法。采用这种淬火方法可以减少和防止淬火工件的变形和开裂 ,并可以在相当程度上解决传统双液淬火方法所存在的凭经验操作的缺点 ,提高淬火工件的产品质量和生产率。     

大型薄形调质钢板热处理冷压淬火畸变控制

大型钢板调质是热处理行业中多年来难以控制变形、淬火变形大、十分棘手的难题之一.在企业没有专用设备的条件下是很难控制变形量的,校平是最大的难题;采用铸铁平板夹压淬火后,工件变形几乎很小,保证了金相组织及硬度,可谓是一种解决实际问题的热处理淬火创新新工艺.经测量40CrMnMo钢板夹压淬火后表面硬度为51～56 HRC.该工艺简单易行,特别适用于中小企业,小批量或单件生产,也可在其他板形工件淬火调质中使用.     

激光淬火连续编程加工方法研究

对翼子板凸模、侧围凹模、发罩内板凹模等模具的激光淬火加工效率和加工过程中工件温度变化,以及工件冷却后变形量进行了深入研究。利用软件编程的高精度、高效率及灵活可控的优势,依托机床精准的伺服驱动系统充分发挥淬火设备智能化的功率及温控系统,取消旧的淬火编程工艺,采用新的编程方式实现激光淬火单光斑程序连续加工,提高激光淬火加工效率,改善工件变形量,降低劳动者（劳动）强度,缩短模具淬火周期。     

L—TEQ处理

L—TEQ处理是在钢材的表面扩散渗氮,于铁—碳合金相图的A_1相变点以下的温度施行淬火,只在表面层相变为马氏体组织,即所谓低温淬火法。因此,由于该工艺具有处理工件的变形小于渗碳处理工件,比氮化处理工件的硬化层厚等优点。通过该工艺,谋求减少工件变形,尺寸变化,作为一种提高耐摩性、表面接触压力强     

XL—ZnCl_2水溶性淬火介质在钳子淬火中的应用试验

采用尖咀钳实物对XL—ZnCl_2水溶性淬火介质的工艺性能以及淬后工件的机械性能进行了试验。结果表明,该介质冷却性能良好,能使工件淬透又可有效地防止开裂、变形,淬后工件的抗弯强度较之油淬提高近一倍。淬火介质使用温度可在10～85℃之间,淬后工件不需清洗,且无污染,成本低,是取代油用予钳子淬火较为理想的淬火介质。     

钢件的淬火热处理变形与控制

综述了钢件热处理变形的影响因素与预防、控制变形的方法.包括四个部分:热处理内应力的组成;热处理变形原因分析;影响热处理变形的因素以及如何预防与控制淬火变形和开裂.     

控制畸变的模压淬火技术与装备

针对淬火过程的畸变问题,介绍了一种有效控制畸变的模压淬火技术与装备。通过控制作用力大小、周期与方式,调整淬火模具的结构与尺寸,控制冷却液的流量、流态及流向等,控制畸变过程,减小工件的畸变,在满足淬火要求的前提下,把模具与机床组合为一体,提供实现淬火过程的模压淬火工艺装备,在保证硬度和金相要求的同时,保持淬火工件的一致性,把淬火质量控制在最佳水平,并付诸工业应用,综合降低了淬火畸变。     

减少离合器壳体淬火畸变的措施

本文分析离合器淬火畸变的主要原因,采取改进工艺路线、工艺参数等措施,有效控制了该零件的淬火畸变,显著降低了零件淬火的废品率。     

Dry and clean age hardening of aluminum alloys by high-pressure gas quenching

When precipitation-hardenable aluminum parts are water quenched, distortion occurs due to thermal stresses. Thereby, a costly reworking is necessary, and for this reason polymer quenchants are often used to reduce distortion, with the disadvantage that the quenched parts have to be cleaned after quenching. In opposition to liquid quenchants, gas quenching may decrease distortion due to the better temperature uniformity during quenching. Furthermore, cleaning of the quenched parts can be avoided because it is a dry process. For this purpose, a heat-treating process was evaluated that included a high-pressure gasquenching step. Gas quenching was applied to different aluminum alloys (i.e., 2024, 6013, 7075, and A357.0), and tensile tests have been carried out to determine the mechanical properties after solution annealing, gas quenching, and aging. Besides high-pressure gas quenching, alloy 2024 was quenched at ambient pressure in a gas nozzle field. The high velocity at the gas outlet leads to an accelerated cooling of the aluminum alloy in this case. Aluminum castings and forgings can be classified as an interesting field of application of these quenching methods due to their near-net shape before the heat treatment. Cost savings would be possible due to the reduced distortion, and therefore, less reworking after the precipitation hardening.     

异型薄壁零件淬火畸变的控制

分析了异型薄壁零件淬火废品率高的主要原因。采取改进工艺、工装设计及淬火后校正3方面措施，有效控制了该零件的淬火畸变，显著降低了零件淬火的废品率。     

Finite element simulation of quench distortion in a low-alloy steel incorporating transformation kinetics

The uncontrolled distortion of steel parts has been a long-standing and serious problem for heat treatment processes, especially quenching. To get a better understanding of distortion, the relationship between transformation kinetics and associated distortion has been investigated using a low-alloy chromium steel. Because martensite is a major phase transformed during the quenching of steel parts and is influential in the distortion, a new martensite start (M_s) temperature and a martensite kinetics equation are proposed. Oil quenching experiments with an asymmetrically cut cylinder were conducted to confirm the effect of phase transformations on distortion. ABAQUS and its user-defined subroutines UMAT and UMATHT were used for finite element method (FEM) analysis. The predictions of the FEM simulation compare well with the measured data. The simulation results allow for a clear understanding of the relationship between the transformation kinetics and distortion.     

A-100钢复杂连接件热处理畸变数值模拟及控制

采用SYSWELD软件对A-100钢复杂连接件进行了有限元建模,对其在无刚性约束条件下淬火过程中温度场和形变进行了模拟仿真,并对模拟结果进行了试验验证。温度场结果表明:冷却0.13 s时温度分布均匀,零件表面温度在820 ℃左右;冷却5~60 s时,零件表面的温度分布极为不均匀,零件头部型腔的棱角处温度较低,而位于底部的支臂与翼面连接处温度较高;而当冷却时间延长至160 s左右时,零件的整体温度已降至60 ℃以下。形变场结果表明:当冷却时间为0.5~10 s时,翼面远离加强筋部位产生较大淬火畸变,顶端棱角处畸变达3 mm;冷却到600 s时,最大畸变量减小至0.65 mm。根据畸变模拟结果设计了专用淬火工装,校形率达到70%左右。     

A comparative study on determination method of heat transfer coefficient using inverse heat transfer and iterative modification

The distortion control of heat-treated steel parts is a main consideration when dealing with hardening by quenching process. Before implementing this heat treating process, prediction of distortion is necessary to be done by experiment and computer simulation for determining a quenching technique which gives the smaller distortion. Temperature-dependent heat transfer coefficient (HTC) estimated from SUS304 cylinder can be determined by both iterative modification of lumped heat capacity method (LumpHC) and inverse heat transfer method (InvHT). Predicted HTC from silver probe is needed for the LumpHC, whereas initial set of assumption is needed for the InvHT. The zone-based HTC estimated from SUS304 cylinder then is employed on S45C cylinder. The prediction accuracy results from both methods are evaluated. As expected, stir quenching gives less distortion than that of still quenching. More accurate prediction of cooling curves, cooling rate curves, and distortion is achieved by employing the LumpHC than that by the InvHT. All analyses were performed by DEFORM-HT 2D.     

浅谈淬火裂纹与畸变的分析及对策

钢铁零件的淬火裂纹和畸变是常见的热处理缺陷,严重时将导致零件报废。以35钢盘状零件和20CrMnTi钢汽车后桥锥齿轮为例,从原材料质量、热处理工艺、淬火介质、工装夹具等方面分析了零件产生淬火裂纹和畸变的原因,提出了预防措施。     

减小GCr15轴承套圈热处理变形的工艺研究

观察了采用铸链炉淬火热处理的GCr15钢轴承套圈淬火前后的金相组织，并观察了其锻造和球化退火后的组织，发现淬火前组织均匀，而淬火后的组织中存在部分屈氏体组织。考虑到生产成本，采用适当升高淬火加热温度、延长保温时间，同时采用压缩空气搅拌冷却淬火介质的方法处理套圈零件，并对比不同方案处理的套圈变形量，发现此方法可以在一定程度上降低套圈的热处理变形，且成本增加很少。