Description : Pick out the wrong statement. (A) Both annealing and normalising release the internal stresses of the material besides improving the mechanical properties (B) Low carbon steel does not respond to ... are also used for surface hardening (D) Martempering of a material is a hardening process
Last Answer : Option C
Description : While normal carburising and nitriding surface treatments increase fatigue strength, excessive treatment may decrease the fatigue strength. Why ?
Last Answer : .Normal carburising/nitriding treatments increase volume due to phase transformation at Surface and introduce residual compressive surface stress and thus increase the fatigue strength. By excessive treatment the ... develop in the regions of high tensile stress and lead to early fatigue failure.
Description : Reduction in the grain size reduces the __________ of the material. (A) Fatigue resistance (B) Tensile strength (C) Creep resistance (D) All (A), (B) & (C)
Last Answer : (C) Creep resistance
Last Answer : (D) All (A), (B) & (C)
Description : ________ cannot increase the fatigue strength of a material. (A) Grain refining (B) Grain coarsening (C) Surface hardening (D) Shot peening
Last Answer : (B) Grain coarsening
Description : The purpose of nitriding the steel is to (A) Harden its surface (B) Soften its surface (C) Improve its reliability (D) None of these
Last Answer : (A) Harden its surface
Description : Statement - 1 : Nitriding is the process of heating steel in presence of `N_(2)` to form iron nirides . Statement -2 : The surface of steel becomes ha
Last Answer : Statement - 1 : Nitriding is the process of heating steel in presence of `N_(2)` to form iron ... Statement-1 : is false , statement-2 : is true
Description : On decreasing the grain size of a polycrystalline material, the property most likely to deteriorate is (A) Creep (B) Toughness (C) Tensile strength (D) Fatigue
Last Answer : (B) Toughnes
Description : Nitriding of steel is done (in electric furnace) at __________ °C. (A) 510 (B) 1720 (C) 2210 (D) 910
Last Answer : (A) 510
Description : Nitriding of steel is a process for (A) Case hardening (B) Spheroidising (C) Normalising (D) Annealing
Last Answer : (A) Case hardening
Description : Pick out the wrong statement. (A) Addition of methane to the furnace atmosphere reduces decarburising by hydrogen (B) Nitrogen in presence of steam decor-burises high carbon steel, whereas hydrocarbon ... the metal surface) cause nitride formation with increase in surface hardness (D) None of these
Last Answer : (D) None of these
Description : The hardenability of steel decreases with (A) Decrease in dislocation density (B) Increase in solutionising temperature (C) Increase in strength (D) Decrease in grain size
Last Answer : D) Decrease in grain size
Description : Failure of a material is termed as fatigue failure, if it fails below the yield point. The resistance to fatigue failure of a material is measured by the (A) Ultimate tensile strength (U.T.S.) (B) Endurance limit (C) Elastic limit (D) None of these
Last Answer : (B) Endurance limit
Description : Fatigue resistance of a material is measured by the (A) Elastic limit (B) Ultimate tensile strength (C) Young's modulus (D) Endurance limit
Last Answer : (D) Endurance limit
Description : spring material should have low (A) Elastic limit (B) Deflection value (C) Fatigue resistance (D) None of these
Last Answer : Option D
Description : Tumbling is the process of improving the __________ of the materials/parts. (A) Surface finish (B) Fatigue limit (C) Creep limit (D) Surface cleanliness
Description : Nitriding is a process of heating steel in atmosphere of :
Last Answer : Nitriding is a process of heating steel in atmosphere of : A. ammonia B. oxygen C. carbondioxide D. air
Description : In cold working of metal as compared to its hot working (A) Cracks and blow holes are eliminated (B) Ductility and impact strength improves (C) Appreciable strain hardening is produced (D) Yield stress, hardness and fatigue strength is not at all affected
Last Answer : (C) Appreciable strain hardening is produced
Description : A material is capable of resisting softening at high temperature, because of its property termed as (A) Hot temper (B) Hot hardness (C) Fatigue (D) Creep
Last Answer : (B) Hot hardness
Description : Temper brittleness of a material can be fairly detected by the __________ test. (A) Fatigue (B) Notched bar impact (C) Tensile (D) Hardness
Last Answer : Option B
Description : The addition of antimony in tin-based alloys improves its (A) Rupture strength and hot hardness (B) Impact strength and bonding strength (C) Deformation resistance (D) Wear resistance
Last Answer : (C) Deformation resistance
Description : The resistance to fatigue of a material is measured by (a) elastic limit (b) Young's modulus (c) ultimate tensile strength (d) endurance limit
Last Answer : (d) endurance limit
Description : The most important property for the spring material is (a) High elastic limit (b) High deflection value (c) Resistance to fatigue and shock (d) All of these
Last Answer : (d) All of these
Description : Chrome vanadium steels usually contain 0.8 to 1.1% Cr, 0.25 to 0.35% C and < 0.25% V. It is (A) Used for making axle & shafts of aeroplanes, automobiles and locomotives (B) ... resistance (C) Having poor toughness (D) Not helpful in producing cleaner steel due to oxidising action of vanadium
Last Answer : (A) Used for making axle & shafts of aeroplanes, automobiles and locomotives
Description : Shock resisting steels should possess high (A) Hardness (B) Toughness (C) Tensile strength (D) Wear resistance
Last Answer : (B) Toughness
Description : Addition of tungsten to steel imparts (A) Magnetic properties (B) Cutting hardness (C) Corrosion resistance (D) Ductility
Last Answer : (B) Cutting hardness
Description : Higher percentage of ash in coal meant for the production of metallurgical grade coke (A) Decreases the hardness of coke (B) Decreases the abrasion resistance of coke (C) Causes brittleness in steel (D) None of these
Description : Deformation that occurs due to stress over a period of time is known as ____________ a) Wear resistance b) Fatigue c) Creep d) Fracture
Last Answer : c) Creep
Description : The ability of materials to develop a characteristic behavior under repeated loading known as ___________ a) Toughness b) Resilience c) Hardness d) Fatigue
Last Answer : d) Fatigue
Description : Maximum hardenability of steel depends upon its (A) Chemical composition (B) Carbon content (C) Grain size (D) Alloying elements content
Description : With increase in the carbon percentage in the steel, its (A) Hardness increases (B) Ductility reduces (C) Tensile strength increases (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : With decrease in the grain size of a material, its creep resistance (A) Increases (B) Decreases (C) Remain constant (D) Either (A) or (B); depends on the material
Last Answer : (C) Remain constant
Description : Increase in ash content of blast furnace coke (A) Reduces its consumption in the furnace (B) Increases its consumption in the furnace (C) Does not affect its consumption in the furnace (D) Decreases its hardness and abrasion resistance
Last Answer : (B) Increases its consumption in the furnace
Description : __________ is not a case hardening process. (A) Carburising (B) Nitriding (C) Cyaniding (D) Annealing
Last Answer : (D) Annealing
Description : Pick the odd man out of the following. (A) Calorising (B) Pack carburising (C) Nitriding (D) Cyaniding
Last Answer : (A) Calorising
Description : Case hardening is not done by (A) Nitriding (B) Hot dipping (C) Electroplating (D) Both ‘b’ & ‘c’
Description : The maximum stress below which a material can withstand an infinite number of cycle of stress, is termed as the (A) Fatigue strength (B) Creep strength (C) Resilience (D) Endurance limit
Last Answer : D) Endurance limit
Description : Fatigue limit improvement by over stressing the metal by successively increasing the load is called coaxing. In fatigue failure, the material fails (A) Below the yield point (B) Above the yield point (C) Below the elastic limit (D) At the elastic limit
Last Answer : Option A
Description : Which of the following is not a characteristic observed in material failure by fatigue fracture? (A) Plastic deformation of material does not occur (B) Initiation of crack from below the surface does ... (D) Presence of both rough & smooth zone with conchoidal markings in smooth zone of the surface
Description : While Normal Carburizing And Nit Riding Surface Treatments Increase Fatigue Strength, Excessive Treatment May Decrease The Fatigue Strength. Why?
Last Answer : Normal carburizes/nits riding treatments increases volume due to phase transformation at the surface and introduce residual compressive surface stress and thus increases fatigue strength. By excessive treatment, the ... in the regions of the high tensile stress and lead o early fatigue failure.
Description : Pick up the correct statement from the following: (A) Catalysts are added to assist and accelerate the hardening of resin (B) The fillers are inert materials and they impart strength and hardness (C) Fibrous fillers increase thermal resistance (D) All the above
Last Answer : Answer: Option D
Description : Weld decay will cause which of the following problems? a) A reduced resistance to corrosion b) a lower tensile strength c) The toughness is reduced d) The hardness will increase
Last Answer : a) A reduced resistance to corrosion
Description : If the grain size of soil increases (A) Surface area decreases (B) Specific retention decreases (C) Water supply in well increases (D) All the above
Description : What will happen if stresses induced due to surge in the spring exceeds the endurance limit stress of the spring. a) Fatigue Failure b) Fracture c) None of the listed d) Nipping
Last Answer : a) Fatigue Failure
Description : When a material is subjected to fatigue loading, the ratio of the endurance limit to the ultimate tensile strength is (a) 0.20 (b) 0.35 (c) 0.50 (d) 0.65
Last Answer : (c) 0.50
Description : Factor of safety for fatigue loading is the ratio of (a) elastic limit to the working stress (b) Young's modulus to the ultimate tensile strength (c) endurance limit to the working stress (d) elastic limit to the yield point
Last Answer : (c) endurance limit to the working stress
Description : Failure of a material is called fatigue when it fails (a) at the elastic limit (b) below the elastic limit (c) at the yield point (d) below the yield point
Last Answer : (d) below the yield point
Description : The endurance or fatigue limit is defined as the maximum value of the stress which a polished standard specimen can withstand without failure, for infinite number of cycles, when subjected to (a) static load (b) dynamic load (c) static as well as dynamic load (d) completely reversed load
Last Answer : (d) completely reversed load