Answer is:
high toughness
Explanation:
shock resisting steel that offers good ductility and toughness at high hardness levels. It exhibits high strength and adequate abrasion resistance for those applications involving shock or impact loading.
Answer is:
Flat machining the face surface around the hole
Explanation:
Spot facing is a machining operation for producing a flat seat for bolt head, washer or nut at the opening of a drilled hole. The tool is called a spot facer or a spot facing tool.
Spot facing is similar to counter-boring, except that it is shallower. Tools that are used for counter-boring can be used for spot facing as well.
