中碳钢凸轮轴热处理工艺设计
时间:2016-12-15 15:13 来源:毕业论文 作者:毕业论文 点击:次
| 设计总说明：本设计主要研究凸轮轴零件的性能要求、选材以及工艺。根据已知的技术要求进行设计。设计感应器、热处理工艺以及所需用到的设备设计选择。设计时，要了解凸轮轴、凸轮轴的性能要求以及一些凸轮轴的材料。不仅如此，掌握感应加热的原理是必须的。由于凸轮以及轴承档的宽度不一致，所以加热方法无法一致。凸轮使用同时加热淬火，轴承档使用连续加热淬火。在感应器的设计方面，对于感应线圈的厚度、内径、外径进行数据计算。中频感应器的汇流条和连接板一般焊接在一起。汇流条取厚为1.8mm的紫铜板制成。根据凸轮轴基础的知识以及所要求的参数，设计凸轮轴的感应加热工艺。依据零件淬硬层深度选择的是中频感应加热，频率定为8kHz。比功率的选择主要取决于频率和要求的硬化层深度。在频率一定时，硬化层较浅的，选用较大比功率；在层深相同情况下，设备频率较低的可选用较大比功率。在比功率一定时，频率越大，加热速度越快；当比功率一定时，频率越高，电流透入式越浅，加热速度越快。感应加热表面淬火是需要计算的功率有发电输出功率、零件加热所需要的总功率、输入到零件的单位表面功率等。单位表面功率是指被加热单位面积上所需要的电功率，它是通过调节电源输出功率来获得的。单位表面功率对零件加热过程有很大影响。单位表面频率是根据频率和被加热零件直径决定的。频率越低，零件直径越小，所需要的单位表面功率越大。再根据所设计的参数选择合适的感应加热淬火设备。同时加热淬火法是将工件的整体或一部分置于感应器之中或其领近位置，感应器接通高频或中频电流，使工件感应加热，待工件加热到淬火温度后，切断电流，立即或间隔一段时间或提前一点时间，对加热部分进行冷却，使该部位达到淬火目的。当零件的淬火面积大于变频设备的同时加热淬火的最大面积时，应采用连续加热淬火法。根据标准选择加热温度，加热速度，保温时间来选择确定淬火机床设备。感应加热的冷却方法的选择是根据钢材、零件形状与尺寸、感应加热的方法等综合考虑的。感应加热时，常用的冷却方法有浸液冷却法和喷射冷却法。由于碳钢及低合金钢制作的零件大多数采用喷射冷却，所以本设计采用喷射冷却法。感应加热的冷却介质的选择是根据钢材、零件形状与尺寸、感应加热的方法等综合考虑决定的。感应淬火最常用的淬火介质是水。水适用于以低淬透性钢所致作的形状简单的零件，用于喷射冷却。感应加热表面淬火后的零件为了降低拉应力，消除脆性，所以还有选择回火。目的是为了降低零件的脆性，提高韧性，减少内应力，防止开裂，防止变形，提高尺寸稳定性，保证机械性能的重要工序。本设计采用炉中回火，选择井式回火炉。 关键词：50Mn；中碳钢；热处理工艺；感应加热淬火 4354 Design of Heat Treatment Process of Medium Carbon Steel Abstract: This design mainly study that performance requirements of camshaft parts, selection and process.Design sensors, heat treatment process and the necessary equipment used in design choices.When you design,it is required to understand the camshaft, camshaft camshaft performance requirements as well as some of the material. Moreover, the control principle of induction heating is necessary.Since the width of the cam and bearing file inconsistent, so the heating method can not consistent. Using simultaneous heating quenching cam bearings file using continuous heating quenching. The design of the sensor, the thickness of the induction coil, diameter, outside diameter data. IF sensor bus bars and plates generally welded together. Take the bus bar is 1.8mm thick plate made of copper. According to basic knowledge of the camshaft and the required parameters, the design of the induction heating process camshaft.According to basic knowledge of the camshaft and the required parameters, the design of the induction heating process camshaft. Based parts hardened layer depth induction heating is selected, the frequency set at 8kHz. The selection of specific power requirements depending on the frequency and depth of hardened layer. The frequency is constant, the hardened layer shallow, use a larger specific power; layers deep in the same case, the device can be used with lower frequency greater than the power. Than the power is constant, the higher the frequency, the faster heating; when the specific power is constant, the higher the frequency, the more shallow type current penetration, heat faster. Induction heating surface hardening is necessary to calculate the power of a power generation output, part of the total power required for heating, into the part of the unit surface power, etc. Power is the unit surface area is needed on the heating unit of electric power, which is the output power by adjusting the power to obtain. Surface power unit during heating of the part has a great influence. Frequency unit surface to be heated according to the frequency determined by the diameter of the part. The lower the frequency, the smaller the diameter parts, the greater the power unit surface required. According to the designed parameters select the appropriate Induction Heating Equipment. While heating the workpiece quenching method is to put the whole or part of the neck near the sensor into its position, the sensor connected to high or medium frequency current, induction heating of the workpiece, the workpiece to be heated to the quenching temperature, cut off the current, immediate or time lag or advance a little time to cool the heating part, so that the parts reach quenching purposes. When parts of the quenching area greater than frequency devices simultaneously hardening the maximum area should be used when continuous heating quenching method. According to the standard selection heating temperature, heating rate, holding time to select quenching machine equipment. Cooling the induction heating method is selected according to steel, part shape and size, a method of induction heating comprehensive consideration. Induction heating, cooling methods are commonly used cooling method immersion and spray cooling method. Because carbon steel and low alloy steel parts made most use of spray cooling, so the design uses spray cooling method. Induction heating of the cooling medium is selected according to the steel, shape and size of parts, induction heating method such as considering the decision. The most common induction hardening quenching medium is water. Water for a low hardenability steels due to the shape of simple parts as for spray cooling. After induction heating surface hardening of parts in order to reduce the tensile stress, eliminating the brittleness, so there select tempering. Purpose is to reduce the brittleness of parts, improve toughness, to reduce internal stress, to prevent cracking, prevent deformation, improved dimensional stability, an important step to ensure the mechanical properties. The design uses a tempering furnace, select Pit Furnace. (责任编辑：qin) |