Engineering Materials interview questions

1. A.depth to which a steel hardens on quenching, measured by the Jominy end-quench test and raised by chromium, molybdenum and manganese
2. B.brittle crack growth from the combined action of tensile stress and a specific corrosive environment, such as chlorides on austenitic stainless steel
3. C.austenite of 0.8% carbon transforming on slow cooling to pearlite, a lamellar mix of ferrite and cementite, at 727 °C
4. D.loss of ductility in high-strength steels when hydrogen absorbed during pickling or plating collects at stress raisers, prevented by baking after plating

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1. A.Fatigue striations
2. B.Eutectoid reaction
3. C.Ductile-brittle transition temperature
4. D.Creep

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1. A.Eutectoid reaction — microscopic ridges on a fracture surface each marking one cycle of crack advance, the signature that confirms a fatigue failure
2. B.Eutectoid reaction — austenite of 0.8% carbon transforming on slow cooling to pearlite, a lamellar mix of ferrite and cementite, at 727 °C
3. C.Eutectoid reaction — brittle crack growth from the combined action of tensile stress and a specific corrosive environment, such as chlorides on austenitic stainless steel
4. D.Eutectoid reaction — chromium above about 11–12% forms an adherent, self-healing Cr₂O₃ film that provides the corrosion resistance

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1. A.temperature below which BCC steels fracture by brittle cleavage, found from Charpy impact tests at falling temperatures
2. B.depth to which a steel hardens on quenching, measured by the Jominy end-quench test and raised by chromium, molybdenum and manganese
3. C.loss of ductility in high-strength steels when hydrogen absorbed during pickling or plating collects at stress raisers, prevented by baking after plating
4. D.hard, brittle body-centred tetragonal phase formed by diffusionless shear transformation when austenite is quenched

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1. A.Stainless steel passivity
2. B.Fatigue striations
3. C.Martensite
4. D.Stress corrosion cracking

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1. A.Martensite — austenite of 0.8% carbon transforming on slow cooling to pearlite, a lamellar mix of ferrite and cementite, at 727 °C
2. B.Martensite — temperature below which BCC steels fracture by brittle cleavage, found from Charpy impact tests at falling temperatures
3. C.Martensite — brittle crack growth from the combined action of tensile stress and a specific corrosive environment, such as chlorides on austenitic stainless steel
4. D.Martensite — hard, brittle body-centred tetragonal phase formed by diffusionless shear transformation when austenite is quenched

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1. A.brittle crack growth from the combined action of tensile stress and a specific corrosive environment, such as chlorides on austenitic stainless steel
2. B.depth to which a steel hardens on quenching, measured by the Jominy end-quench test and raised by chromium, molybdenum and manganese
3. C.temperature below which BCC steels fracture by brittle cleavage, found from Charpy impact tests at falling temperatures
4. D.hard, brittle body-centred tetragonal phase formed by diffusionless shear transformation when austenite is quenched

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1. A.Stress corrosion cracking
2. B.Eutectoid reaction
3. C.Ductile-brittle transition temperature
4. D.Stainless steel passivity

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1. A.Ductile-brittle transition temperature — loss of ductility in high-strength steels when hydrogen absorbed during pickling or plating collects at stress raisers, prevented by baking after plating
2. B.Ductile-brittle transition temperature — chromium above about 11–12% forms an adherent, self-healing Cr₂O₃ film that provides the corrosion resistance
3. C.Ductile-brittle transition temperature — temperature below which BCC steels fracture by brittle cleavage, found from Charpy impact tests at falling temperatures
4. D.Ductile-brittle transition temperature — time-dependent plastic deformation under constant stress, significant above about 0.4 of the absolute melting temperature

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1. A.depth to which a steel hardens on quenching, measured by the Jominy end-quench test and raised by chromium, molybdenum and manganese
2. B.time-dependent plastic deformation under constant stress, significant above about 0.4 of the absolute melting temperature
3. C.temperature below which BCC steels fracture by brittle cleavage, found from Charpy impact tests at falling temperatures
4. D.hard, brittle body-centred tetragonal phase formed by diffusionless shear transformation when austenite is quenched

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1. A.Fatigue striations
2. B.Hardenability
3. C.Ductile-brittle transition temperature
4. D.Creep

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1. A.Hardenability — loss of ductility in high-strength steels when hydrogen absorbed during pickling or plating collects at stress raisers, prevented by baking after plating
2. B.Hardenability — brittle crack growth from the combined action of tensile stress and a specific corrosive environment, such as chlorides on austenitic stainless steel
3. C.Hardenability — microscopic ridges on a fracture surface each marking one cycle of crack advance, the signature that confirms a fatigue failure
4. D.Hardenability — depth to which a steel hardens on quenching, measured by the Jominy end-quench test and raised by chromium, molybdenum and manganese

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1. A.hard, brittle body-centred tetragonal phase formed by diffusionless shear transformation when austenite is quenched
2. B.loss of ductility in high-strength steels when hydrogen absorbed during pickling or plating collects at stress raisers, prevented by baking after plating
3. C.temperature below which BCC steels fracture by brittle cleavage, found from Charpy impact tests at falling temperatures
4. D.time-dependent plastic deformation under constant stress, significant above about 0.4 of the absolute melting temperature

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1. A.Fatigue striations
2. B.Hardenability
3. C.Hydrogen embrittlement
4. D.Creep

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1. A.Creep — time-dependent plastic deformation under constant stress, significant above about 0.4 of the absolute melting temperature
2. B.Creep — chromium above about 11–12% forms an adherent, self-healing Cr₂O₃ film that provides the corrosion resistance
3. C.Creep — brittle crack growth from the combined action of tensile stress and a specific corrosive environment, such as chlorides on austenitic stainless steel
4. D.Creep — austenite of 0.8% carbon transforming on slow cooling to pearlite, a lamellar mix of ferrite and cementite, at 727 °C

Answer + AI explanation with Pro

1. A.loss of ductility in high-strength steels when hydrogen absorbed during pickling or plating collects at stress raisers, prevented by baking after plating
2. B.time-dependent plastic deformation under constant stress, significant above about 0.4 of the absolute melting temperature
3. C.chromium above about 11–12% forms an adherent, self-healing Cr₂O₃ film that provides the corrosion resistance
4. D.microscopic ridges on a fracture surface each marking one cycle of crack advance, the signature that confirms a fatigue failure

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1. A.Hydrogen embrittlement
2. B.Stainless steel passivity
3. C.Fatigue striations
4. D.Eutectoid reaction

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1. A.Stainless steel passivity — chromium above about 11–12% forms an adherent, self-healing Cr₂O₃ film that provides the corrosion resistance
2. B.Stainless steel passivity — depth to which a steel hardens on quenching, measured by the Jominy end-quench test and raised by chromium, molybdenum and manganese
3. C.Stainless steel passivity — temperature below which BCC steels fracture by brittle cleavage, found from Charpy impact tests at falling temperatures
4. D.Stainless steel passivity — austenite of 0.8% carbon transforming on slow cooling to pearlite, a lamellar mix of ferrite and cementite, at 727 °C

Answer + AI explanation with Pro

1. A.microscopic ridges on a fracture surface each marking one cycle of crack advance, the signature that confirms a fatigue failure
2. B.depth to which a steel hardens on quenching, measured by the Jominy end-quench test and raised by chromium, molybdenum and manganese
3. C.time-dependent plastic deformation under constant stress, significant above about 0.4 of the absolute melting temperature
4. D.brittle crack growth from the combined action of tensile stress and a specific corrosive environment, such as chlorides on austenitic stainless steel

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1. A.Ductile-brittle transition temperature
2. B.Creep
3. C.Fatigue striations
4. D.Stainless steel passivity

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1. A.Fatigue striations — brittle crack growth from the combined action of tensile stress and a specific corrosive environment, such as chlorides on austenitic stainless steel
2. B.Fatigue striations — chromium above about 11–12% forms an adherent, self-healing Cr₂O₃ film that provides the corrosion resistance
3. C.Fatigue striations — microscopic ridges on a fracture surface each marking one cycle of crack advance, the signature that confirms a fatigue failure
4. D.Fatigue striations — time-dependent plastic deformation under constant stress, significant above about 0.4 of the absolute melting temperature

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1. A.loss of ductility in high-strength steels when hydrogen absorbed during pickling or plating collects at stress raisers, prevented by baking after plating
2. B.depth to which a steel hardens on quenching, measured by the Jominy end-quench test and raised by chromium, molybdenum and manganese
3. C.microscopic ridges on a fracture surface each marking one cycle of crack advance, the signature that confirms a fatigue failure
4. D.time-dependent plastic deformation under constant stress, significant above about 0.4 of the absolute melting temperature

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1. A.Ductile-brittle transition temperature
2. B.Hydrogen embrittlement
3. C.Hardenability
4. D.Eutectoid reaction

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1. A.Hydrogen embrittlement — time-dependent plastic deformation under constant stress, significant above about 0.4 of the absolute melting temperature
2. B.Hydrogen embrittlement — austenite of 0.8% carbon transforming on slow cooling to pearlite, a lamellar mix of ferrite and cementite, at 727 °C
3. C.Hydrogen embrittlement — chromium above about 11–12% forms an adherent, self-healing Cr₂O₃ film that provides the corrosion resistance
4. D.Hydrogen embrittlement — loss of ductility in high-strength steels when hydrogen absorbed during pickling or plating collects at stress raisers, prevented by baking after plating

Answer + AI explanation with Pro

1. A.brittle crack growth from the combined action of tensile stress and a specific corrosive environment, such as chlorides on austenitic stainless steel
2. B.time-dependent plastic deformation under constant stress, significant above about 0.4 of the absolute melting temperature
3. C.hard, brittle body-centred tetragonal phase formed by diffusionless shear transformation when austenite is quenched
4. D.depth to which a steel hardens on quenching, measured by the Jominy end-quench test and raised by chromium, molybdenum and manganese

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1. A.Stainless steel passivity
2. B.Ductile-brittle transition temperature
3. C.Fatigue striations
4. D.Stress corrosion cracking

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1. A.Stress corrosion cracking — brittle crack growth from the combined action of tensile stress and a specific corrosive environment, such as chlorides on austenitic stainless steel
2. B.Stress corrosion cracking — chromium above about 11–12% forms an adherent, self-healing Cr₂O₃ film that provides the corrosion resistance
3. C.Stress corrosion cracking — microscopic ridges on a fracture surface each marking one cycle of crack advance, the signature that confirms a fatigue failure
4. D.Stress corrosion cracking — depth to which a steel hardens on quenching, measured by the Jominy end-quench test and raised by chromium, molybdenum and manganese

Answer + AI explanation with Pro