Shaanxi Yunzhong Industry Development Co.,Ltd
Address: NO.128 Gaoxin Road, Baoji City, Shaanxi Province of China
Eight provisions of the heat treatment of metal
1, divided into two
Different materials, different equipment, different technological parameters, the heat treatment of the organization and the quality is also different.
Even if the material grade, equipment, process parameters are the same, because of the lower limit of the chemical composition content, the lower limit of the heat treatment temperature, the lower limit of the heat treatment time, the heat treatment of the organization and the quality will be different.
Even chemical composition content limit, heat treatment temperature limit, thermal insulation time limits are the same, due to the heat treatment of pre hot and cold processing technology, quality, organization, etc. different heat treatment and quality also will be different.
Therefore, after the problem, to specific issues specific analysis, that is to be divided into two.
Two, 2 plans
Fe-C phase diagram and C curve
Fe-C phase diagram is a necessary knowledge to deal with iron and steel, C curve is the heat of titanium plates cooling after the transformation of the organization chart, these two maps are the basis of heat treatment.
Only grasp the two maps, in-depth understanding of these two maps, heat treatment to be able to start.
3, three process
That is, heating, thermal insulation, cooling the three processes.
These three processes run through all the heat treatment process, the three processes of the quality of the
final heat treatment determines the quality of good or bad. These three processes are well understood, and the heat treatment is a primer.
4, four fire
Annealing and normalizing, quenching and tempering.
These four fire is the most conventional heat treatment, the four fire is good or bad, to a certain extent, reflects the level of heat treatment. If the four fire is good, it is a heat treatment technician.
5, five organizations
Namely, austenite, martensite, martensite, bainite, pearlite.
Deep understanding of the characteristics of the five organizations, organizational form, precipitation
(formation) conditions, performance, etc., heat treatment technology level can be improved.
Six, 6 major defects
Six flaws: oxidation, decarburization, overheating, burning, deformation and cracking.
Among them, in most taboo burn off and cracking defect, because these two defects is irreparable defects and
the other four should also try to avoid, although able to compensate, but significantly increased the
workload and cost of production.
Engage in heat treatment to avoid or reduce the six major defects, is a qualified heat treatment engineer.
7, seven phase transitions
(1) pearlite transformation to austenite (P, A);
(2) the transformation of austenite to pearlite (A, P);
(3) the transformation of austenite to martensite (A, S);
(4) the austenite is transformed to the (A - T);
(5) the transformation of austenite to martensite (A, M);
(6) the transformation of austenite to bainite (A, B);
(7) martensite transformed into tempered martensite (M - M).
Grasp the seven phase change, heat treatment is a high level of.
8, eight Technology
Namely: annealing, normalizing, quenching and tempering process, surface quenching process, chemical heat treatment process and vacuum heat treatment technology, special heat treatment process (laser, ion nitriding, PVD and CVD, ion plating, etc.).