कठोरता और लचीलेपन का वांछित संतुलन प्राप्त करने के लिए किस प्रकार के कर्तन उपकरण (cutting tool) को आमतौर पर 230°C तक गर्म करके टेम्पर्ड (tempered) किया जाता है?

The softest and most ductile condition of steel is obtained by which of the following processes?

If steel is cooled in still air during heat treatment, the structure obtained is:

Which of the following statements are true regarding the annealing of steels? 1. Steels are heated to 500 to 700°C. 2. Cooling is done slowly and steadily. 3. Internal stresses are relieved. 4. Ductility of steel is increased. Select the correct answer using the options given below: