Casting Heat Treatment
Explore how Precisionvast utilizes advanced heat treatment processes to enhance the mechanical properties and durability of our castings. This page provides insights into our heat treatment techniques and their role in achieving optimal material characteristics
Why heat treat precision castings?
Precisionvast precision casting heat treatment capabilities
Investment Casting Heat Treating
Precisionvast offers a wide range of heat treating services. With a long history of specialized heat treating partnerships, we are able to offer the following low cost heat treating methods:
1. Annealing:
Heating steel to a temperature slightly above the critical temperature, holding it at that temperature for a certain period of time, and then cooling it slowly with the furnace.
Annealing purpose:
soften the steel parts for cutting; improve the plasticity and toughness of steel, so that the steel can be successfully cold stamping or cold drawing process; refine the grain, improve the organization in order to improve the mechanical properties of steel; to eliminate the previous stage of mechanical processing (casting, forging, welding, hot rolling, cold drawing, etc.) residual stresses, to prevent deformation of the steel parts or cracking.
2. Normalizing:
Heating temperature and holding time is similar to annealing, the difference is that normalizing is cooled in the air, the cooling rate is greater than the cooling rate of the annealing, can be obtained than the annealed organization organization is finer, so as to obtain higher mechanical properties (hardness and strength are higher than annealing).
Normalizing purpose:
The final heat treatment of ordinary structural parts (no longer quenching and tempering) low carbon structural steel preheating treatment to obtain the appropriate hardness, to facilitate the subsequent cutting process (normalizing in the air outside the furnace cooling, more economical, can be used to replace the annealing of normalizing); high-carbon steel normalizing treatment can be used as a preheat treatment before other heat treatment.
3. Tempering:
Quenched parts, re-heating to a temperature below Ac1, after holding for a certain period of time, and then placed in the air, water or oil cooling heat treatment process.
Tempering purpose:
To eliminate quenching due to cooling too fast and produce internal stress, reduce the brittleness of steel, and make the steel parts have a certain toughness. Tempering is always carried out in conjunction with quenching and is not a separate process.
4. Quenching Quenching (Integral Quenching):
Heating the steel to a temperature of 30-500C above AC1 or AC3, holding for a certain period of time, and then cooling rapidly in water or oil.
Quenching purpose:
To get high hardness martensite organization, improve the hardness and wear resistance of the parts, quenching is usually followed by tempering treatment, the purpose is to eliminate the internal stresses of the steel parts and obtain a variety of different mechanical properties of the tempered organization.
5. Hydrogen removal treatment:
The purpose is to remove hydrogen and improve the plasticity of cast steel parts.
Carburizing treatment:
Carburizing quenching is applicable to mild steel and low alloy steel, the first to improve the carbon content of the surface layer of the part, after quenching the surface layer to obtain high hardness, while the heart still maintains a certain degree of strength and high toughness and plasticity. Carburizing the whole carburizing and local carburizing. Local carburizing part of the non-carburized part to take anti-seepage measures (copper-plated or plated anti-seepage material). Due to carburizing quenching deformation, and carburizing depth is generally between 0.5-2mm, so the carburizing process is generally arranged between semi-finishing and finishing. The process route is generally: material – forging – normalizing – rough, semi-finishing – carburizing quenching – finishing.
When the partial carburization parts of the non-carburized part of the use of increased margin, the removal of excess carburized layer of the process program, the removal of excess carburized layer of the process should be arranged in the carburization, before quenching.
6. Tempering and quenching:
Quenching and tempering composite heat treatment process for investment casting parts. This heat treatment is usually used to improve the surface hardness and internal hardness of precision investment castings. Particularly suitable for the replacement of worn parts.
7. Surface hardening:
Also known as surface hardening, this method is to inject hardening elements into the surface of the investment castings, thus providing an additional protective layer.
8. Chemical heat treatment
The workpiece will be placed in a certain medium heating and insulation, so that the medium of the active atoms penetrate the surface layer of the parts to change the chemical composition and organization of the surface layer, so that the surface layer of the workpiece with some special mechanical or physical and chemical properties of the heat treatment process. Chemical heat treatment process classification: carburizing, nitriding, carbonitriding, etc..
Carburizing must be quenched and low-temperature tempering.
Nitriding is suitable for parts that are not subject to impact, but need to be wear-resistant and corrosion-resistant, such as gears (especially internal gears), spindles, boring bars, precision screws, gauges, molds and so on.
precisionvast foundry investment casting Heat Treatment!
These are the main heat treatment methods for investment casting. Heat treatment is mainly based on the usage of investment casting. If you are not familiar with heat treatment, it doesn’t matter, if your product needs this service, our engineers will provide you with the right advice. If you need our heat treatment service, please contact us.