ME Manufacturing Processes and Surface Engineering

Question 1

In metal casting, porosity defects are primarily caused by:

Accepted Answer

Gas entrapment and solidification shrinkage

Answer

Excessive mold temperature

Answer

Too slow a pouring rate

Answer

Use of green sand molds

Question 2

Hot working of metals is defined as plastic deformation carried out at temperatures:

Accepted Answer

Above the recrystallization temperature, so recrystallization occurs concurrently

Answer

Below the recrystallization temperature, preserving strain hardening

Answer

At exactly the melting point of the alloy

Answer

At room temperature under high strain rates

Question 3

In powder metallurgy, sintering after compaction serves to:

Accepted Answer

Bond powder particles together and reduce porosity via solid-state diffusion

Answer

Remove alloying elements from the compact

Answer

Increase the density of the powder before pressing

Answer

Coat particles with a protective oxide layer

Question 4

Which welding process uses a non-consumable tungsten electrode and an inert shielding gas to weld reactive metals like titanium and aluminum?

Accepted Answer

Gas Tungsten Arc Welding (GTAW/TIG)

Answer

Shielded Metal Arc Welding (SMAW)

Answer

Gas Metal Arc Welding (GMAW/MIG)

Answer

Flux-Cored Arc Welding (FCAW)

Question 5

Electroplating deposits a metal coating on a substrate by:

Accepted Answer

Electrolytic reduction of metal ions from solution onto the cathode (workpiece)

Answer

Physical vapor deposition in vacuum

Answer

Thermal spraying of molten metal droplets

Answer

Chemical vapor deposition from a metal halide precursor

Question 6

Anodizing of aluminum creates a surface layer of:

Accepted Answer

Aluminum oxide (Al2O3) formed by controlled electrochemical oxidation

Answer

Pure aluminum deposited from an electrolytic bath

Answer

Zinc chromate conversion coating

Answer

Nickel phosphate for corrosion protection