CNC Machining Quenching Steel Parts
Quenching Service Of Steel Is a Heat Treatment Process That Heat The Steel To The Temperature Above The Critical Temperature Ac3 ( Hypoeutectoid Steel ) Or Ac1 (Hypereutectoid Steel) For a Period Of Time To Austenite It In Whole Or In Part, And Then Cool It To The Temperature Below Ms (Or Near Ms) At a Cooling Rate Greater Than The Critical Cooling Rate For Martensite ( Or Bainite ) Transformation.
In General, The Solid Solution Treatment Of Aluminum Alloy, Copper Alloy, Titanium Alloy, Toughened Glass And Other Materials Or The Heat Treatment Process With Rapid Cooling Process Is Called Quenching.
Quenching Is a Heat Treatment Process In Which Steel Is Heated To Above Critical Temperature For a Certain Period Of Time And Then Cooled At a Cooling Rate Greater Than The Critical Cooling Rate To Obtain Unbalanced Structure Dominated By Martensite (Also Bainite Or Retaining Single-Phase Austenite As Required). Quenching Is The Most Widely Used Process In Steel Heat Treatment Process.
Objective
The Purpose Of Quenching Is To Transform The Undercooled Austenite Into Martensite Or Bainite, Obtain Martensite Or Bainite Structure, And Then Cooperate With Tempering At Different Temperatures To Greatly Improve The Rigidity, Hardness, Wear Resistance, Fatigue Strength And Toughness Of Steel, So As To Meet The Different Application Requirements Of Various Mechanical Parts And Tools. It Can Also Meet The Special Physical And Chemical Properties Such As Ferromagnetism And Corrosion Resistance Of Some Special Steels By Quenching.
The Metal Workpiece Is Heated To a Suitable Temperature For a Period Of Time, And Then Immersed In The Quenching Medium For Rapid Cooling Of The Metal Heat Treatment Process. Commonly Used Quenching Media Are Brine, Water, Mineral Oil, Air And So On. Quenching Can Improve The Hardness And Wear Resistance Of Metal Workpieces, So It Is Widely Used In Various Industries, Dies, Measuring Tools And Parts Requiring Wear-Resistant Surface (Such As Gears, Rolls, Carburized Parts, Etc.).
Through Quenching And Tempering At Different Temperatures, The Strength, Toughness And Fatigue Strength Of Metals Can Be Greatly Improved, And The Combination Of These Properties (Comprehensive Mechanical Properties) Can Be Obtained To Meet Different Application Requirements. In Addition, Quenching Can Also Make Some Special Properties Of Steel To Obtain Certain Physical And Chemical Properties, Such As Quenching Makes Permanent Magnet Steel Enhance Its Ferromagnetism, Stainless Steel Improve Its Corrosion Resistance And So On. Quenching Process Is Mainly Used For Steel Parts.
When The Commonly Used Steel Is Heated Above The Critical Temperature, The Original Structure At Room Temperature Will Be All Or Most Transformed Into Austenite. Subsequently, Steels Are Immersed In Water Or Oil For Rapid Cooling, And Austenite Is Transformed Into Martensite. Compared With Other Structures In Steel, Martensite Has The Highest Hardness. Rapid Cooling During Quenching Will Cause Internal Stress In The Workpiece. When It Reaches a Certain Extent, The Workpiece Will Be Distorted Or Even Cracked. Therefore, a Suitable Cooling Method Must Be Chosen. According To The Cooling Method, Quenching Process Can Be Divided Into Four Categories: Single Liquid Quenching, Double Medium Quenching, Martensite Stepped Quenching And Bainite Isothermal Quenching.