Engineering Materials

Cold rolled steel sheets contain carbon of the following order___________________? A. 0.1% B. 0.2% C. 0.4% D. 0.6% E. 0.8%

Which of the following element results in presence of free graphite in C.I_________________? A. carbon B. sulphurC. silicon D. manganese E. phosphorous

The machinability of steel is increased by___________________? A. silicon and sulphurB. phosphorous, lead and sulphur C. sulphur, graphite and aluminium D. phosphorous and aluminium E. none of the above

Blast furnace produces following by reduction of iron ore_______________? A. cast ironB. pig iron C. wrought iron D. malleable iron E. white iron

Melting point of iron is__________________? A. 1539°C B. 1601°C C. 1489°C D. 1712°C E. 1131°C

Which of the following elements does not impart hardness to steel__________________? A. copper B. chromium C. nickel D. silicon E. none of the above

Nodular iron has____________________? A. high maehinability B. low melting point C. high tensile strength D. good fluidityE. all of the above

The hardness of steel increases if it contains____________________? A. austeniteB. martensite C. pearlite D. cementite E. all of the above

Cobalt in steel __________________? A. improves wear resistance, cuttinability and toughness B. refines grain size and produces les tendency to carburisation, improve corrosion and heat resistant proper tiesC. improves cutting ability and reduce hardenability D. gives ductility, toughness, tensile strength and anti corrosion property: E. none of the above

Tensile strength of steel can be safely in-creased by________________? A. adding carbon up to 2.8% B. adding carbon up to 6.3%C. adding carbon up to 0.83% D. adding small quantities of copper E. adding copper and carbon