基于ad 的电容触摸按键电路设计
The fourth chapter is the heat treatment of steel
reviewing and thinking
A glossary of the
1. heat treatment
Heat treatment is the process of heating, holding and cooling metal materials or workpieces in an appropriate way to obtain desired structure and properties.
2. isothermal transformation
Isothermal transformation refers to the pha transition of undercooled austenite when the workpiece is isothermally retained in a certain temperature range below the critical point.
3. continuous cooling transformation
中国十大名小吃Continuous cooling transformation refers to the pha transformation of undercooled austenite when th
e workpiece is cooled at different cooling rates after austenitizing.
4. martensite
Martensite is supersaturated solid solution of carbon or alloy
校长不要啊
elements in alpha -Fe.
5. annealing
Annealing of steel is a heat treatment process that heats the workpiece to a proper temperature, keeps it for a certain time and then cools slowly.
6. normalizing
Normalizing refers to the heat treatment process that the workpiece is heated and cooled in the air after austenitizing.
7. quenching
Quenching of steel is the process of heat treatment to obtain martensite or (or) bainite structure by c
ooling the workpiece in an appropriate way after austenitizing.
8. tempering
Tempering refers to the heat treatment process that the workpiece is hardened and heated to a certain temperature below Ac1, holding for a certain period of time and then cooling to room temperature.
9. surface heat treatment
Surface heat treatment is to change the structure and properties of the surface of the workpiece, only the surface of the heat treatment process.
10. carburizing
In order to improve the carbon content of the workpiece surface and form a certain carbon content gradient in it, the chemical heat treatment process of carburizing and holding the workpiece in the carburizing medium and permeating the carbon atoms is called carburizing.
11. the nitriding
In a certain temperature, the chemical heat treatment process that makes the nitrogen atoms penetrate into the surface of the workpiece in a certain medium is called nitriding, also called nitriding.
Two, fill in the blanks
1. the overall heat treatment can be divided into annealing, normalizing, quenching and tempering. The
2. according to the different heating methods, surface quenching methods are mainly: induction heating surface quenching, flame heating surface quenching, electric contact heating surface quenching, electrolyte heating surface quenching, etc.. The
3. there are many chemical heat treatment methods, usually named by infiltration elements, such as carburizing, nitriding, carbonitriding and boriding. The
The 4. heat treatment process consists of three stages: heating, holding and cooling. The
During the isothermal transformation of 5. eutectoid steel, the products of high temperature transformation are P, S and T. The
豆腐丸子的做法6. bainite is divided into two kinds: upper bainite and lower bainite. The
7. quenching methods are: single medium quenching, double medium quenching, martensite classification quenching and bainite isothermal quenching. The
8. commonly ud annealing methods are: full annealing, spheroidizing annealing and stress relieving annealing. The
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9. commonly ud cooling media are water, oil, air and so on. The
10. common quenching defects are overheating and over burning, oxidation and decarburization, hardness and soft point,
Deformation and cracking, etc..电磁炉品牌
The 11. induction heating surface hardening method, according to the current frequency is different, can be divided into the high frequency induction heating surface quenching, intermediate frequency induction heating surface hardening and frequency induction heating surface quenching three. Moreover, the higher the induction heating current frequency is, the shallower the hardened layer is. According to the 12. tempering
temperature range can be divided into low temperature tempering, tempering temperature and tempering temperature and tempering three. The
教师招聘自我介绍13. chemical heat treatment is compod of three basic process: decomposition, adsorption and diffusion. The
14. according to the different physical state of carburizing medium, carburizing method can be divided into gas carburizing, liquid carburizing and solid carburizing three kinds. The
Three, the choice
1. undercooling austenite is the austenite that has not been changed at C temperature.
A.Ms;
B. Mf;
黄河简介C. A1. The
Two
The quenching heating temperature of the eutectoid steel should be chon at A, while the hypo eutectoid steel should be chon at C. The
A. Ac1+30 to 50 DEG C; above
B.. Accm;
C.. Ac3+3 0 to 50 DEG C. The
3. quenching and tempering treatment is the heat treatment of
C. The
A. quenching + low temperature tempering;
B. quenching + medium在线硬件检测
