Surface heat treatment refers to a metal thermal processing process in which the chemical composition and structure of the material surface are changed by means of heating, heat preservation and cooling in a solid state to obtain the required properties. The following are six surface heat treatment methods.
Surface hardening
The workpiece is heated rapidly by different heat sources, and when the surface temperature of the part reaches above the critical point (at this time, the core temperature of the workpiece is below the critical point), it is rapidly cooled, so that the surface layer of the workpiece gets a hardened structure while the core remains the original organize. The most widely used in industry is induction heating and flame heating surface hardening.
Chemical heat treatment
The workpiece is heated and kept warm in a medium containing active elements, so that the active atoms in the medium penetrate into the surface of the workpiece or form a covering layer of a certain compound to change the structure and chemical composition of the surface, so that the surface of the part has special mechanical properties. or physicochemical properties. For example, nitriding treatment, nitriding treatment refers to a chemical heat treatment process that makes nitrogen atoms penetrate into the surface of the workpiece in a certain medium at a certain temperature. Nitrided products have excellent wear resistance, fatigue resistance, corrosion resistance and high temperature resistance.
Contact resistance heating quenching
A voltage of less than 5 volts is applied to the workpiece through the electrode, a large current flows through the contact between the electrode and the workpiece, and a large amount of resistance heat is generated to heat the surface of the workpiece to the quenching temperature, and then the electrode is removed, and the heat is transmitted Into the interior of the workpiece and the surface is rapidly cooled, that is, to achieve the purpose of quenching.
Electrolytic heating and quenching
The workpiece is placed in the electrolyte of acid, alkali or salt solution, the workpiece is connected to the cathode, and the electrolytic cell is connected to the anode. After the direct current is connected, the electrolyte is electrolyzed, oxygen is released on the anode, and hydrogen is released on the workpiece. Hydrogen forms a gas film around the workpiece and becomes a resistor to generate heat, rapidly heating the surface of the workpiece to the quenching temperature, then the power is turned off, the gas film disappears immediately, and the electrolyte becomes a quenching medium, which rapidly cools and hardens the surface of the workpiece.
Laser heat treatment
The application research of laser in heat treatment began in the early 1970s, and then entered the production application stage from the laboratory research stage. When the focused high energy density (10W/cm) laser irradiates the metal surface, the metal surface rises to the quenching temperature within a few hundredths of a second or even a few thousandths of a second.
Electron beam heat treatment
Electron beam surface hardening has the same characteristics as laser except that it should be carried out in vacuum. When the electron beam hits the metal surface, the point of impact is heated rapidly. The depth to which the electron beam penetrates the material depends on the accelerating voltage and the material density.
Chuangtuo Jinggong (Jiangsu) Co., LTD is profession manufacturer of various types of Hexagon Nuts, everything is customized in our factory, Should you have any questions please feel free to come back to us.
Contact: Lorena
Email: market@chtofastener.com
Mobile: 0086 153 6641 6606 (Wechat/Whatsapp ID)
LET'S GET IN TOUCH
Privacy statement: Your privacy is very important to Us. Our company promises not to disclose your personal information to any external company with out your explicit permission.
Fill in more information so that we can get in touch with you faster
Privacy statement: Your privacy is very important to Us. Our company promises not to disclose your personal information to any external company with out your explicit permission.