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What is heat Treatment ?

HEAT TREATMENT

•          It is a continuous process of HEATING, HOLDING AT A PARTICULAR TEMPERATURE FOR SPECIFIC TIME AND COOLING AT A PREDETERMINED RATE of metals to change their physical and mechanical properties, without letting it change its shape. . The most common application is metallurgical. Heat treatment could be said to be a method for strengthening materials but could also be used to alter some mechanical properties such as improving formability, machining, etc. It is very important manufacturing processes that can not only help manufacturing process but can also improve product, its performance, and its characteristics in many ways.

•          Engineering properties are modified by heat treatment processes so that structural components are able withstand specified operating conditions and have desired useful life.

The properties of steel can be improved by changing its structure at atomic level. This can be achieved through

i)              By Alloying Elements
ii)             By Heat Treatment

 a same type of steel can exhibit different type of properties under different heat treatment conditions. Such type of flexibility helps us to decide various manufacturing processes and ultimate uses of steel.

DETAILS OF HEAT TREATMENT

1.       Heating -> Rate of Heating
2.       Soaking -> Temp. & time of Soaking
3.       Cooling -> Rate & Medium of cooling

-               The properties of steel can be influenced by different combinations of the above parameters
-               Different composition and initial phases of material can also be influenced the properties after Heat Treatment.

PURPOSE OF HEAT TREATMENT

(1)     Soften the metal prior to shaping or cutting / Machining. 
(2)     Relieve the effects of strain hardening that occurs during cold forming.
(3)     Achieve the final strength and hardness required in the finished product as one of the end manufacturing processes.

TYPE OF HEAT TREATMENT

·         Body heat treatment
·         Surface heat treatment

TYPE OF THERMAL TREATMENT

  1. Annealing.
  2. Normalizing
  3. Hardening & Tempering.
  4. Stress Relieving
  5. Surface Hardening.



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