影响感应淬火质量的几个因素

正1.感应淬火工艺分析感应淬火提供了一种快速在线的热处理加工方法,其热效率高,加热时间短,工件变形小,无氧化脱碳,易于进行局部热处理,实现清洁生产,与冷加工共线,实现"一个流"生产。表面加热淬火,必须以快速加热为前提,即在很短的时间内将工件表层加热到临界点以上并完成奥氏体化,而感应过渡区以里的心部则处于低温状态,继而冷却淬火,从而使表面硬化。处理的工件具有更高的表面硬度和残余压应力,因而在扭转载荷下表现出更优异的强度和抗疲劳性能。由于感应淬火可以选择的频率段较多,工频、中频、超音频、高频、超高频,硬化层的范围比较     

微机控制立式高频淬火机床的改造设计

目前,一般轴类工件的高频淬火都采用工件在固定的感应器和喷火圈中匀速运动,边加热边冷却,完成连续淬火。复杂工件的高频淬火大都靠制作与工件形状尺寸相近的感应器来实现。这大多局限于轴径比变化不大的轴类工件。对于长阶梯轴类工件,做与工件形状尺寸相近的感应器是不可能的,如用一般轴类工件的连续淬火方法,由于工件外径不等,工件与感应器的间隙不同,在阶梯轴各段表层被加热的温度也有差异,致使工件各处的硬度不均匀,这就对热处理装置提出了改进的要求。我们知道,在感应器感应频率恒定的条     

轴类工件感应加热表面淬火感应器设计制作要领浅析

感应器是感应加热表面淬火的主要设施,它的作用是,通过感应电流将高、中频电能传导到工件表面上,达到对工件进行表面热处理的目的。 感应器的设计通常是在设备参数确定的前提下进行的,在使用中仅存在参数的选择、调整使之互相匹配以达到满意的效果。     

汽车零件感应热处理技术的发展

感应热处理是利用电磁感应现象将零件表面迅速加热到临界温度以上,使表面奥氏体化,然后采用喷淬或浸淬的方式,使表面快速冷却到马氏体相变区完成相变硬化。感应热处理的基本特征是: (1)加热仅限于表层 由于交变电流的集肤效应,感应加热集中于零件表面,从而仅使零件表层产生强化,避免了整体加热所带来的能量损失。因此感应热处理相对于普通热处理能耗大大降低。 (2)可方便实施表面局部强化 根据零件使用性能要求,在零件局部表面实施感应加热硬化,赋     

重载齿轮轴感应淬火技术研究应用

通过对重载齿轮轴进行渗碳、调质及感应淬火试验研究,分析讨论了不同电流频率感应淬火对齿轮轴表面硬度、齿根硬度、齿心部硬度、硬度梯度、金相组织的影响。研究表明,18Cr2Ni4WA钢齿轮轴渗碳、调质加感应淬火,可以有效提高工件表面硬度至58 HRC以上,并整体提高淬硬层硬度梯度值,改善硬化层的金相组织;同时,确保齿心部硬度最佳,提高齿轮轴的弯曲疲劳强度。对含有较多Cr、Ni、W、Mo等低碳合金钢齿轮材料,提供了可提高产品质量的一种热处理工艺方法。     

一种驱动轮轴感应淬火工艺试验应用研究

拖拉机驱动轮轴在工作中受力大且复杂,容易发生早期断裂。针对某型号拖拉机在装配试车时,发生驱动轮轴齿条断裂和键槽开裂掉块现象,我们从金属材料及热处理等方面对其产生原因进行了分析。结果表明,驱动轮轴的齿条、键槽壁部位为感应淬火疑难部位,该部位在感应淬火时易产生淬火裂纹。通过感应淬火工艺调整和改进,避免了感应淬火裂纹的产生,并使驱动轮轴感应淬火硬化层深符合技术要求,满足了用户对驱动轮轴的正常使用要求。为驱动轮轴类零件结构设计、工艺流程设计和热处理技术要求提供有效的指导。     

变速感应淬火的示教再现控制

针对机床轴类工件外锥面或内锥孔进行连续感应淬火时存在的淬火硬度和有效硬化层不均匀等质量问题，采用电液比例阀调节淬火移动速度的方法保持淬火加热温度并通过示教再现控制保证工艺的稳定性与再现性。     

感应热处理过程的实时监测

在当今的工业领域，感应加热已经成为非常普遍和重要的热处理手段，众多的感应加热设备在世界上被大规模地使用。每年，感应热处理市场上诞生出数以百计的新设备，汽车制造商和他们的零部件供应商是这个快速、可重复的淬火方案的主要用户。感应加热能够在非常短的时间内完成工件表面淬火，这是该项技术在过去30年内迅速发展并广泛应用的重要原因之一。然而，人们对产品感应热处理过程的质量监测和跟踪需求的日益增加，对感应加热设备制造商们提出的研究和建立相应质量监测系统的需求，需要对零件热处理参数进行更好的掌控，可靠的记录并存储这些数据。这种过程监测可由破坏性或非破坏性测试系统来完成，提供了不同层面的连续质量控制方案（能量计算、信号分析等）。易孚迪（EFD）感应设备集团，作为欧洲最大的感应加热制造商，研究和制造了各种用于感应加热处理领域的质量监测产品。     

解决轴类感应淬火端头裂纹的有效方法

我们热处理分厂有感应加热设备4台,其中中频机组两台,100kW、60kW高频各一台。每年这4台设备处理各种淬火轴类零件8～10万件,其废品率为2.5%～3.0%,主要是由端头裂纹所致,此外,还有30%左右的不合     

淬火液及冷却水实现零排放的新工艺

本文介绍了沈阳机床集团热处理分厂在整体搬迁过程中，选用空气冷却器对热处理淬火介质和感应加热设备冷却水进行封闭式循环冷却，实现了热处理淬火介质和冷却水的零排放目标；同时保证了热处理工件的质量和提高了生产效率及减少了维修量，这方面取得了预期的节能减排的效果。     

34CrNi3Mo齿轮轴锻后热处理工艺改进

针对大截面34CrNi3Mo齿轮轴热处理过程中常出现的硬度偏高和生产厂家复检强度不合格问题进行分析和研究,提出了起伏等温退火等改进措施并应用于实际生产中,结果表明,该工艺方案明显改善了工件热处理质量,提高了产品的使用寿命。     

GCr15钢表面强化层耐磨性能研究进展

GCr15钢广泛应用于轴承、传动链销轴及工模具制造行业。常规热处理的低硬度使其在服役过程表面易发生磨损失效,采用表面强化技术可有效的提高GCr15钢的表面硬度及耐磨性。归纳介绍国内外GCr15钢的表面强化方法,总结激光表面处理、离子注入、喷涂技术、气相沉积、化学热处理等5种强化方法的特点,综述5种强化方法在改善GC515钢耐磨性能方面的研究成果。探讨不同表面处理方法对GCr15钢耐磨性能的影响,展望GCr15钢表面强化技术的发展方向。     

Y54插齿机上插制轴齿斜齿轮的精度保证

通过对废旧Y54插齿机维修,加高改装,安装螺旋导轨,调整刀架及工作台蜗轮副,选用合适的刀具、切削液、设计合理的夹具,并对工件的材料正火热处理工序加以控制,达到了插制轴斜齿轮的精度要求,满足了生产需要。     

Analysis of surface roughness and cutting force components in hard turning with CBN tool: Prediction model and cutting conditions optimization

In this study, the effects of cutting speed, feed rate, workpiece hardness and depth of cut on surface roughness and cutting force components in the hard turning were experimentally investigated. AISI H11 steel was hardened to (40; 45 and 50) HRC, machined using cubic boron nitride (CBN 7020 from Sandvik Company) which is essentially made of 57% CBN and 35% TiCN. Four-factor (cutting speed, feed rate, hardness and depth of cut) and three-level fractional experiment designs completed with a statistical analysis of variance (ANOVA) were performed. Mathematical models for surface roughness and cutting force components were developed using the response surface methodology (RSM). Results show that the cutting force components are influenced principally by the depth of cut and workpiece hardness; on the other hand, both feed rate and workpiece hardness have statistical significance on surface roughness. Finally, the ranges for best cutting conditions are proposed for serial industrial production.     

四点接触球转盘轴承许用接触应力试验

42CrMo钢具有良好的淬硬性,被广泛用做转盘轴承套圈材料。首先对42CrMo钢采取不同热处理工艺进行表面感应淬火,以获得不同的淬硬层深度;然后通过电子万能试验机进行压痕试验;最后对试验数据进行分析研究。研究发现:决定转盘轴承许用接触应力的因素除了材料的机械性能外,还包括材料热处理后的表面硬度、淬硬层深度以及轴承的结构参数等因素。     

Inertia friction welding process analysis and mechanical properties evaluation of large rotor shaft in marine turbo charger

The two aims of this study are first, determining the optimal welding process parameters by using the finite element simulation and second, determining the optimal tempering temperature by evaluating the mechanical properties of friction welded part for manufacturing large rotor shaft. Inertia welding was conducted in order to make the large rotor shaft of turbo charger for low speed marine diesel engine. The rotor shaft is composed of the 310mm diameter disk and the 140mm diameter shaft. Since diameters of disk and shaft are very different, the integration using friction welding reduces manufacturing cost compared with the forming process of which a disk and shaft are forged into one body. Finite element simulation was performed, because inertial welding friction process depended on many process parameters, including axial force, initial revolution speed and energy, amount of upset, and working time. It is expected that this modeling will significantly reduce the number of experimental trials needed when determining the optimal welding parameters. Inertia welding was carried out with optimal process parameter conditions obtained from the simulation results. Welded joint part, made by friction welding, had very poor mechanical properties, and so it required heat treatment. The base material used in the investigation was SFCMV1 (SANYO special steel, high strength low alloy Cr-Mo steel) of 140mm diameter. In the study, heat treatment test carried out quenching (950 °C, 4hr, oil cooling) and tempering (690–720 °C, 6hr, air cooling) for friction welding specimens. The various tests, including microstructure observation, tensile, hardness, and fatigue tests, were conducted to evaluate the mechanical properties under various heat treatment conditions after inertia welding.     

汽车齿轮锻造毛坯预热处理工艺的改进

介绍了低碳合金渗碳钢齿坯预热处理工艺的现状 ,讨论了钢件的正火组织和硬度对切削加工性能及渗碳淬火变形的影响 ,提出应推广应用等温正火技术以改进齿坯预热处理质量。     

Effects of cutting edge geometry, workpiece hardness, feed rate and cutting speed on surface roughness and forces in finish turning of hardened AISI H13 steel

In this study, the effects of cutting edge geometry, workpiece hardness, feed rate and cutting speed on surface roughness and resultant forces in the finish hard turning of AISI H13 steel were experimentally investigated. Cubic boron nitrite inserts with two distinct edge preparations and through-hardened AISI H13 steel bars were used. Four-factor (hardness, edge geometry, feed rate and cutting speed) two-level fractional experiments were conducted and statistical analysis of variance was performed. During hard turning experiments, three components of tool forces and roughness of the machined surface were measured. This study shows that the effects of workpiece hardness, cutting edge geometry, feed rate and cutting speed on surface roughness are statistically significant. The effects of two-factor interactions of the edge geometry and the workpiece hardness, the edge geometry and the feed rate, and the cutting speed and feed rate also appeared to be important. Especially honed edge geometry and lower workpiece surface hardness resulted in better surface roughness. Cutting-edge geometry, workpiece hardness and cutting speed are found to be affecting force components. The lower workpiece surface hardness and honed edge geometry resulted in lower tangential and radial forces.     

95CrMo锥形钎杆热处理工艺的探索

通过对95CrMo钎杆经过相同的温度加热保温,分别进行风冷、空冷、缓冷,以及两种不同加热方式处理之后,对比四种工艺处理的差异及与中空钢原材料的检验分析比较,研究表明在相同中空钢原材料的前提下,随着冷却速度的加快,沿晶碳化物级别越低,硬度越高;在相同加热温度和冷却条件下,感应加热处理的珠光体类型组织比井式炉加热处理的珠光体类型组织更细。