Hot runner processing is divided into: normalizing, annealing, solution heat treatment, solution treatment, aging treatment, quenching, tempering, steel carbonitriding, quenching and tempering ten aspects. The following will explain one by one hot runner system these ten aspects:
1. Normalizing: The steel or steel heating to the critical point AC3 or ACM above the appropriate temperature to maintain a certain period of time after cooling in air to obtain pearlite heat treatment organizations.
2. Annealing annealing: The sub-eutectoid steel workpiece heated to AC3 above 20-40 degrees, after holding for a period of time, with the furnace slowly cooling (or buried in the sand or lime cooling) to 500 degrees below the heat in the air cooling process
3. Solution heat treatment: the alloy is heated to a high temperature single-phase zone to maintain a constant temperature, the excess phase to fully dissolve into the solid solution, and then quickly cooled to obtain supersaturated solid solution heat treatment process
4. Aging: After the alloy solution heat treatment or cold plastic deformation, at room temperature or slightly higher than the room temperature to maintain its performance over time and the phenomenon.
5. Solution treatment: make the alloy fully dissolved in various phases, strengthen the solid solution and improve the toughness and corrosion resistance, eliminate stress and softening, in order to continue processing
6. Aging: Precipitation in the strengthening phase of the heating temperature and insulation, so that precipitated enhanced phase precipitation, to be hardened to improve the strength
7. Quenching: austenitizing the steel at an appropriate cooling rate of cooling, so that the workpiece cross-section in all or within a certain range of martensite and other unstable tissue structure of the heat treatment process changes
8. Tempering: the quenched workpiece heated to the critical point AC1 below the appropriate temperature to maintain a certain period of time, followed by cooling with the required method to obtain the desired structure and performance of the heat treatment process
9. Steel carbonitriding: Carbonitriding is the process of infiltrating carbon and nitrogen into the surface of steel. Traditionally, carbonitriding, also known as cyanidation, is currently used in a wide range of applications including gas-phase carbonitriding and cryogenic gas carbonitriding (gas nitrocarburizing). The main purpose of gas-phase carbonitriding is to increase the hardness, wear resistance and fatigue strength of the steel. Low-temperature gas carbonitriding mainly nitriding, its main purpose is to improve the wear resistance and seizure resistance of steel.
10. Quenching and tempering quenching and tempering: the general practice of quenching and tempering combined heat treatment is called quenched and tempered. Quenching treatment is widely used in a variety of important structural parts, especially those working under alternating load linkages, bolts, gears and shafts. Quenched tempered sorbite after tempering, its mechanical properties than the same hardness of orthoclase sorbite is better. Its hardness depends on the high temperature tempering temperature and the tempering stability of steel and workpiece cross-sectional size, generally between HB200-350.
11. Brazing: the heat treatment process of bonding two kinds of workpieces together with brazing material 【Suzhou Mold Casting】