Maharsh Metal Heat Treatment

SOLUTION ANNEALING  MMHT can accomplish solution annealing heat treatment of stainless steel product in open fire, atmosphere or vacuum depending on the material and required surface finish. All furnaces meet AMS 2750 class 5 specifications for temperature uniformity & pyrometry.
Size capabilities depend on atmosphere requirements and temperature.
Maximum Open Fire Capacity: 72” x 36” x 144”
Maximum Vacuum Capacity: 72” x 36” x 36”
Maximum Atmosphere Capacity: 96” x 60” x 48”
Process
The process of solution annealing is typically applied to stainless steels and high nickel alloys for heat resistant and corrosion resistant applications. These are generally high temperature processes requiring rapid quenching. The most common application of the solution annealing process is used for austenitic stainless steels. Solution annealing 300 series stainless steels improves corrosion resistance by putting carbides into solution in the micro structural matrix.
A rapid quench inhibits carbides from reforming during cooling. Austenitic stainless steels are not solution annealed to appreciably change mechanical properties.
Many other materials receive solution annealing for reasons of changing mechanical properties. Some materials, such as 17-4 stainless steel & some Inconels, are solution annealed as a pre-treatment for age hardening. This ultimately provides the required mechanical properties for the part application.
Recommendations
Selection of the proper atmosphere is a critical factor when choosing proper processing parameters for solution annealing. If no oxidation is allowable a vacuum process should be selected.
ALUMINUM SOLUTION ANNEALING
Solution annealing is a high temperature heat treat process where the alloying elements of the material are brought into a solid solution. The solid solution condition is maintained by quenching the material in water or polymer. Aluminum in the solution annealed condition is in a soft state allowing the material to be readily formed or straightened to the required shape or straightening tolerance.
Capability
MMHT   has multiple solution annealing furnaces to meet your heat treating needs. All aluminum furnaces are surveyed to meet AMS 2750E class 3 temperature requirements of +/-10F. ThermTech has furnaces capable of running work up to 72” horizontally and 74” vertically.
Process
Solution annealing is a relatively high temperature heat treating process typically run at temperatures between 915F and 990F. The material is held at the temperatures for a period of time necessary to bring the alloying elements into a solid solution. Typical times range from 20 minutes to several hours depending on the material and section thickness. The material is quenched in water or polymer retaining the material in the solid solution state. The relatively high processing temperature coupled with the rapid cooling often results in some degree of distortion. Post solution anneal straightening may be required prior to the age hardening process.
Recommendations
Solution anneal heat treating is required for aluminum alloys for age hardening to be effective. Distortion is often a concern due to the elevated heat treating temperatures and rapid cooling in water or polymer. Post solution anneal straightening may be necessary before the material is age hardened. MMHT  has many years of experience creating fixtures and racking solutions to minimize the risk of distortion. Additionally, MMHT  has extensive straightening capabilities to meet your post solution anneal straightness tolerances.

Additional Information:

• Item Code: 005
• Production Capacity: 100 TUNE/MONTH
• Delivery Time: 3-5 DAYS

Annealing
Annealing is a heat treatment process which alters the microstructure of a material to change its mechanical or electrical properties. Typically, in steels, annealing is used to reduce hardness, increase ductility and help eliminate internal stresses.
Benefits
Annealing will restore ductility following cold working and hence allow additional processing without cracking. Annealing may also be used to release mechanical stresses induced by grinding, machining etc. hence preventing distortion during subsequent higher temperature heat treatment operations. In some cases, annealing is used to improve electrical properties.
Application & materials
One of the main applications of annealing is reversing the effects of work hardening. During cold forming, drawing, bending etc. the material can become hardened to the point where further working can be impossible or result in cracking. An annealing operation at this stage will make the material more ductile, permitting further forming. In a similar manner, annealing is utilized to remove the internal stresses which occur when welds solidify.
Besides steels, other metals may also benefit from annealing such as copper, aluminium, and brass.
Process details
Annealing is a generic term and can be further classified according to temperature and atmosphere.
For steels, subcritical annealing takes place at 1000°F – 1200°F, so there is no crystal structure change. Intermediate annealing is carried out at 1200°F – 1400°F, so there is some transformation to austenite and full annealing involves completely austenitizing the work at 1500°F – 1700°F.
Parts can be annealed in a vacuum or reducing atmosphere where a bright surface finish is needed. Annealing in air is employed where surface finish is not an important factor and an endothermic/neutral atmosphere may be used during annealing to control decarburisation.

Additional Information:

• Item Code: 006
• Production Capacity: 65 TONE/MONTH
• Delivery Time: 3-4 DAYS