Engineering Materials Questions

• Heat treatment — best description of the spheroidising process in steel Which option most closely describes the common procedure used to spheroidise cementite in medium/high-carbon steels to improve machinability and toughness?
• Aluminium casting metallurgy — effect of silicon on fluidity and castability Assess the statement: “Aluminium has low density, and adding silicon improves its melt fluidity and, therefore, its castability.”
• Free-machining aluminium — which addition most increases machinability? The machinability (chip breaking, tool life, surface finish) of aluminium is most improved by adding which of the following?
• Fe–C microstructures — identify the incorrect statement Which of the following statements about steel microstructures is WRONG?
• Cast iron impurities — which element makes cast iron hard and brittle? Among common impurities in cast iron, which one most strongly promotes hardness and brittleness (hot shortness) when present in excess?
• German silver (nickel silver) — identify the presence of silver What does “German silver” (also known as nickel silver) contain with respect to elemental silver?
• Alloying in high-speed steels (HSS) — effect of manganese In traditional tungsten/molybdenum high-speed steels, manganese is added primarily to toughen the steel and to increase its which property?
• Crystal structures — which metals are body-centred cubic (BCC) at room temperature? Select the correct group that primarily exhibits the BCC lattice among the listed options.
• Manganese in low-carbon steels — primary benefits For low-carbon steels, manganese is added mainly to achieve which combination of property improvements?
• Mechanical property most desirable for tools and machine members in service For materials used in tools and machine components, which fundamental property is most desirable so that parts return to original shape after load removal?
• Alloying for corrosion resistance in steels — role of Ni and Cr State whether the statement is correct: “Corrosion resistance of steel is increased by adding nickel and chromium.”
• Bearing materials — selection for heavy loads and low-to-moderate speeds Which material is most suitable for plain bearings subjected to heavy loads (typically at lower speeds), where higher compressive strength is required?
• Carbon in iron — terminology for free carbon State whether the statement is correct: “In iron, the presence of carbon in free (uncombined) form is called graphite.”
• Cast iron strengths — comparison of compressive and tensile values For cast iron, the compressive strength is generally __________ its tensile strength.
• Allotropic iron — temperature range for gamma (γ) iron Gamma-iron (austenite) occurs in pure iron between which of the following temperature ranges?
• Wrought iron — characteristic properties Which of the following statements correctly describes wrought iron?
• Cast iron metallurgy: Which impurity element in cast iron most strongly promotes graphitisation (graphite formation) and also increases the fluidity of the molten metal during casting?
• Design for impact loading: Which material property is most desirable for components that must absorb shock and impact without fracturing?
• Indian steel designation (IS): According to Indian standards, the plain carbon steel marked as 40C8 indicates a carbon content in the range of:
• Automotive design materials: A connecting rod for internal combustion engines is usually manufactured from which class of steel to achieve strength with good forgeability and fatigue resistance?