Reasons and Solutions for Abnormal Color of Products Heat Treated in Vacuum Furnace
Vacuum furnace is the mainstream equipment in heat treatment industry at present. Its products are not only reliable in quality, but also environmentally friendly, pollution-free, and do not need three wastes treatment. At the same time, energy consumption is significantly lower than traditional heat treatment equipment such as salt bath furnace. Therefore, vacuum furnace is widely used in aerospace, weapons, electronics, automotive, machinery industry and other fields. But it is often seen that users of vacuum furnaces post on the Internet asking about the wrong color of products produced by heat treatment of vacuum furnaces. This problem is a common problem in heat treatment production. Today, Xiaobian gives you a brief analysis of the causes and solutions of the wrong color of products processed by vacuum furnaces, hoping to help you.
First of all, we can detect whether the vacuum furnace equipment itself leaks, which can be determined by the pressure rise rate index of the vacuum furnace; here we need to remind you that when testing the pressure rise rate, we must bake the oven before cooling to room temperature, and then test, but can not open the door and then vacuum.
Secondly, check whether there is leakage in the intake pipeline of the vacuum furnace. Sometimes we test the pressure rise rate of the vacuum furnace to show normal, but there is leakage in the intake pipeline or valve of the vacuum furnace. The pressure in the intake pipeline is gradient, and the closer to the end of the furnace body, the more negative pressure is. This also leads to the wrong color of the products processed by the vacuum furnace.
Thirdly, we can detect that the purity of inert gas into the vacuum furnace equipment is not high enough. When the purity of inert gas is not enough, the oxygen mixed into the inert gas will lead to oxidation and decarbonization of the product, which will lead to discoloration of the product. The purity of the detected gas can be directly detected or concluded through comparative tests with other equipment.
Finally, the humidity in the vacuum furnace equipment is attached to the inner wall of the vacuum furnace or on the heat exchanger, which is difficult to discharge through the oven drying method. When the vacuum furnace equipment does not exist the above three problems, the color of the product is mostly caused by this reason; at this time, we can raise the vacuum furnace equipment to high temperature, stop heating, and then. High purity inert gas is injected into the furnace, and then the fan circulation system is started. The wet gas adhering to the inner wall of the vacuum furnace and the heat exchanger is baked by high temperature and hot air in the vacuum furnace to solve this problem.