Aluminium alloys tend to get their strength from precipitation hardening, work hardening and solute hardening. what can you infer about the hall-petch slope of aluminium? 6. why are covalently and ionically bonded materials usually brittle?

Steel is coated with a thin layer of ceramic to protect against corrosion. what do you expect to happen to the coating when the temperature of the steel is increased significantly? explain.

What are the two (02) benefits, which may result from a successful implementation of preventive maintenance (pm) program in an organization? (clo3)a)- lean manufacturing b)-overlapping responsibilities c)-the planner is not qualified d)-accurate contractor information e)-reduction in equipment redundancies f)-accurate stores information

The catalogue for a refrigerant 22, four-cylinder, hermetic compressor operating at 29 r/s. a condensing temperature of 40°c and an evaporating temperature of -4°c shows a refrigeration capacity of 115 kw. at this operating point, the motor (its efficiency is 90 percent) draws 34.5 kw. the bore of the cylinders is 87 mm and the piston stroke is 70 mm. the performance data are based on 8°c of sub-cooling of the liquid leaving the condenser. compute (a) the actual volumetric efficiency and (b) the compression efficiency.