中频感应加热炉淬火的目的

中频感应加热炉淬火的目的如下：

1、提高零件表面的耐磨性 中频感应加热炉淬火最初应用于曲轴颈表面，其目的就 是为提高曲轴颈的耐磨性，在此以前曲轴釆用调质处理，中频感应加热炉淬火使曲轴颈的 耐磨性大大提高。发动机凸轮轴的凸轮与轴颈，燃油泵的凸轮轴早期都是采用 渗碳淬火的，中频感应加热炉淬火由于快速，低成本，在线生产等原因取代了渗碳淬火工 艺。铸铁气缸套早期是整体淬火的，中频感应加热炉淬火以其自动化，高生产率等优势取 代了旧工艺。

2、提高零件的疲劳强度中频感应加热炉淬火进一步的应用是提高淬火件的疲劳强 度。例如汽车半轴，以EQ1092汽车半轴为例，在土3000N - m转矩载荷下，疲 劳试验200万次，仍然完好无损，而原来调质处理，半轴的疲劳寿命不到30万 次；又如万向节球头销原工艺为18CrMnTi钢渗碳淬火，后改用45钢中频感应加热炉淬火， 零件的弯曲疲劳寿命从8万次提高到200万次以上。曲轴圆角淬火则使曲轴的疲 劳强度提高一倍，有些产品的曲轴疲劳强度达到700MPa以上。

3、减少中频感应加热炉加热畸变 特别是齿轮类零件，渗碳齿轮由于工艺时间长, 淬火后畸变大；而齿轮中频感应加热炉淬火，特别是同步双频(SDF)齿轮淬火，工艺时间 短，畸变小，使齿轮精度提高，噪声减低。我国也有渗碳内齿轮因畸变大而改 为中频感应加热炉淬火的实例。

4、节能、节材等采用低淬透性钢制造齿轮等零件，进行中频感应加热炉淬火。首 先是钢材无合金元素，节省了材料费用，再者是局部加热淬火，时间短，因此节能效果显著；自动化在线生产节省了劳动力、无油污、无有害气体排放则更 加保护环境。

5、取代深层渗碳 深层渗碳是周期长、电耗大的工艺，近年来国外已研 发成功用中频感应加热炉淬火来取代。其效益是：钢材成本降低，节能，省工时（渗碳与 冷加工磨削），减少畸变。

因此，可得出如下结论：

1）应用中频感应加热炉加热对工件进行表面淬火，使原来工件的耐磨性大大提高。

2）和普通整体淬火件相比，中频感应加热炉淬火件由于表面硬度高和不脱碳，其耐磨 性提高了。

3）用中碳钢制造的中频感应加热炉淬火件的耐磨性，由于表层硬度和碳含量均较低, 其耐磨性比渗碳淬火件低。

The purpose of induction heating furnace quenching

The purpose of induction heating furnace quenching is as follows:

1. Improve the wear resistance of the parts surface. Induction heating furnace quenching was originally applied to the surface of the crankshaft journal. Its purpose was to improve the wear resistance of the crankshaft journal. In the past, the crankshaft was quenched and tempered, and the induction heating furnace quenched the crankshaft journal. The abrasion resistance is greatly improved. The cams and journals of engine camshafts and the camshafts of fuel pumps were all carburized and quenched in the early days. Induction heating furnace quenching replaced the carburizing and quenching process due to rapid, low-cost, online production and other reasons. In the early days, cast iron cylinder liners were integrally quenched. Induction furnace quenching replaced the old process with its advantages of automation and high productivity.

2. Improve the fatigue strength of parts. The further application of induction heating furnace quenching is to improve the fatigue strength of quenched parts. Take the EQ1092 automobile half shaft as an example. Under the soil torque load of 3000N-m, the fatigue test is 2 million times, and it is still intact, but the original quenching and tempering treatment, the fatigue life of the half shaft is less than 300,000 times; Another example is that the original process of the universal joint ball head pin is 18CrMnTi steel carburizing and quenching, and then it is quenched by 45 steel induction heating furnace. The bending fatigue life of the parts is increased from 80,000 times to more than 2 million times. Crankshaft fillet quenching doubles the fatigue strength of the crankshaft, and the fatigue strength of some products reaches 700MPa or more.

3. Reduce the heating distortion of the induction heating furnace, especially gear parts. The carburized gear has a large distortion after quenching due to the long process time; while the gear induction heating furnace quenching, especially the synchronous dual frequency (SDF) gear quenching, has a short process time and distortion Small, improve gear accuracy and reduce noise. In our country, there are also instances where carburized internal gears are changed to induction heating furnace quenching due to large distortion.

4. Use low-hardenability steel to manufacture gears and other parts for energy-saving and material-saving, etc., for induction heating furnace quenching. The first is that the steel has no alloying elements, which saves material costs, and the second is local heating and quenching, which takes a short time, so the energy saving effect is significant; automated online production saves labor, no oil pollution, no harmful gas emissions, and even more protects the environment.

5. Replacing deep carburizing Deep carburizing is a process with long cycle and high power consumption. In recent years, foreign countries have successfully used induction heating furnace quenching to replace it. The benefits are: steel cost reduction, energy saving, labor-saving (carburizing and cold working grinding), and reduced distortion.

Therefore, the following conclusions can be drawn:

1) The surface quenching of the workpiece is heated by the induction heating furnace, which greatly improves the wear resistance of the original workpiece.

2) Compared with ordinary integral quenched parts, induction heating furnace quenched parts have improved wear resistance due to high surface hardness and no decarburization.

3) The wear resistance of induction heating furnace quenched parts made of medium carbon steel is lower than that of carburized quenched parts due to the low surface hardness and carbon content.