Micro-alloyed steels, which are often referred to as High-Strength Low-Alloy Steels (HSLA), are a family of materials strengthened by the elements niobium, vanadium and titanium added either singly or in combination.
The micro alloying elements are sometimes used in conjunction with other strengtheners such as boron, molybdenum and chromium, nickel and copper and their use is invariably accompanied by strict control of impurities such as sulfur, oxygen, nitrogen and phosphorus.
By using a controlled cooling process after hot forging, micro alloy steel can achieve tensile strength range from 800 MPA to 1200 MPA, and thus, micro alloy are gaining popularity replacing low alloy steel that need to be quenched and tempered to improve its strength. Also, by eliminating the need for heat treatment, problems associating with heat treatment such as distortion, and quench cracking are eliminated as well.
Micro alloy steel has gained popular acceptance in automotive industries, and are used to made products such as wheel hub, crankshaft, connecting ord, control arm, and etc.