The hottest mold design needs to know some simple

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Mold design needs to understand some simple heat treatment

Introduction to the basic concepts of heat treatment

1. "Heat treatment"

` heat treatment of steel is a processing process that applies different heating, insulation and cooling to the steel in the solid state, so as to change its internal structure and obtain the required performance. In most heat treatment processes, the purpose of steel heating

'is mainly to obtain austenite structure. Because the disadvantage is that it is quite tragic to fall on the ground. In this habit, the process of heating steel from room temperature structure to austenite like

' state is called austenization of steel. According to different heating and cooling methods, the most basic types can be divided into annealing, normalizing, quenching and tempering

II. Annealing

1 Annealing concept:

the so-called annealing our company adopts the imported grating displacement meter, which is the heat treatment process of heating the metal or alloy to an appropriate temperature, holding it for a certain period of time, and then cooling slowly with the

furnace. Its essence is to heat and austenitize the steel for pearlite transformation

2. Annealing purpose:

(1) Reduce the hardness of steel and improve the plasticity, so as to facilitate cutting and cold deformation processing

(2). Refine the grain, eliminate the structural defects caused by forging, welding, etc., homogenize the structural composition of the steel, improve the properties of

steel or prepare for future heat treatment

`(3). Eliminate internal stress in steel to prevent deformation or cracking

3. Annealing methods:

common annealing methods include complete annealing, spheroidizing annealing, stress relief annealing, recrystallization annealing, diffusion

annealing and isothermal annealing

(1). Complete annealing: weighing crystallization annealing is an annealing process that austenitizes the iron carbon alloy completely and then cools it slowly to obtain a near equilibrium structure. It is applicable to medium carbon steel and medium carbon alloy steel with carbon content of 0.3% - 0.6%

(2). Spheroidizing annealing: annealing process for spheroidizing carbides in steel. Commonly used spheroidizing annealing includes ordinary spheroidizing annealing and isothermal spheroidizing annealing. This process is mainly used for mold, measuring tool and cutting tool steel of eutectoid steel and eutectoid steel

`(3). Stress relief annealing: an annealing process to remove the residual stresses caused by plastic deformation processing, forging, welding, etc. and stored in forgings

(4). Recrystallization annealing: also known as intermediate annealing, it refers to the heat treatment process in which the metal after cold deformation is heated to the recrystallization temperature of

and maintained for an appropriate time to recrystallize the deformed grains into uniform equiaxed grains, so as to eliminate the deformation strengthening and residual stress

(5). Isothermal annealing: it is a heat treatment process that heats the steel parts or blanks to a temperature higher than AC3 (or AC1), keeps them for an appropriate time, cools them to a certain temperature in the pearlite temperature range quickly and keeps them isothermal, so that austenite turns into pearlite structure, and then cools them in air. This annealing method is mainly used for alloy steels with relatively stable supercooled austenite

III. normalizing

1 Normalizing concept:

normalizing is to heat the steel or steel parts to 30~50 ℃ above AC3 (or ACCM) for an appropriate time

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