Q10Basic Mechanical Engineering
Question
2 marks
Q.10. What is 18:4:1 steel? State its application.
Answer
18:4:1 steel represents a standard High-Speed Steel (HSS) alloy composition, crucial for maintaining hardness at extreme cutting temperatures.
The designation 18:4:1 specifically identifies the major alloying elements in this classic High-Speed Steel (HSS): 18% Tungsten, 4% Chromium, and 1% Vanadium (along with approx 0.7% Carbon and the rest Iron). Application: Because the massive tungsten content provides incredible 'red hardness' (the ability to stay sharp and hard even when glowing red hot from friction), it is universally used for heavy-duty metal cutting tools such as lathe single-point cutting tools, milling cutters, drill bits, and broaches.