Vermicular graphite is an undesirable microstructural feature in the ductile iron; however it is the desired type of graphite in: A White cast iron B Malleable cast iron C Gray cast iron D Compacted graphite cast iron E None of the above D Compacted graphite cast iron The carbon equivalent value for a 3.5 wt. % C cast iron containing 1.5 wt. % Si and 0.1wt. % P. A 3.50 % B 4.03 % C 4.50 % D 4.00 % E None of the above B 4.03 % We typically expect the strength of a cast iron to A Increase when the carbon equivalent increases B Decrease when the carbon equivalent increases C Be unaffected by the carbon equivalent D None of the above B Decrease when the carbon equivalent increases According to the AFS-ASTM A247 standard, the following graphite flake pattern is produced by the slow solidification of a hypereutectic grey cast iron: A Type A B Type II C Type C D Type D E Type I F None of the above E Type I Suppose you treat liquid iron with magnesium, innoculate, then wait 10 minutes before pouring. If you produce a white cast iron microstructure instead of ductile iron, then you expect the A Nodularizating element faded B Inoculating agent faded C None of the above B Inoculating agent faded Production of the following alloy cast iron requires addition of 20 wt. % Ni: A Ferritic cast iron B Austenitic cast iron C Pearlitic malleable cast iron D Nodular cast iron E None of the above B Austenitic cast iron According to ISO 5922, the following designation W 45-10 is for the following malleable cast iron: A This is a blackheart malleable cast iron with a minimum tensile strength of 450 MPa and % elongation of 10% B This is a blackheart malleable cast iron with a minimum tensile strength of 45P MPa and % elongation of 10% C This is a whiteheart malleable cast iron with a minimum tensile strength of 450 MPa and % elongation of 10% D This is a whiteheart malleable cast iron with a minimum tensile strength of 45P MPa and % elongation of 10% C This is a whiteheart malleable cast iron with a minimum tensile strength of 450 MPa and % elongation of 10% Which of the following types of cast irons is endangered by fast solidification rate? A Gray B Plain carbon C Nodular cast D White cast iron D white cast iron which of the following phases are said to be metastable? A Austenite B Pearlite C Cementite D Ferrite E Martensite C cementite, and martensite What range of carbon defines Fe-C as cast iron? A 0.02 - 2.0 wt% B 2.0 - 6.67 wt% C 0.0 - 0.8 wt% D 99 - 100 wt% B 2.0 - 6.67 wt% Which of these alloys are used for service temperatures in the range between 500℃ and 1,000℃? A Cast irons B Lead and its alloys C Stainless steels D Aluminum and copper alloys E Refractory alloys F None of the above E Refractory alloys The wing of an aircraft made out of a metal alloy is an example of a A Cast product B Wrought product C Both cast and wrought D None of the above B Wrought product An automotive engine block is an example of a A Cast product B Wrought product C Both cast and wrought D None of the above A Cast product What is the average carbon content of AISI 1080 steel? A 0.30 wt.% C B 0.10 wt.% C C 0.60 wt.% C D 0.80 wt.% C D 0.80 wt.% C which of the following statements best describes cast irons? A High purity iron B An alloy of silicon in iron C An alloy of carbon in iron D Precious metals C An alloy of carbon in iron What range of carbon percentages defines Fe-C alloy as steel? A 0.02 - 2.0 wt.%C B 2.0 - 6.67 wt.%C C 0.0 - 2.0 wt.%C D 0.0 -.8 wt.%C A 0.02 - 2.0 wt.%C What is the average carbon content of AISI 4330 steel? A 0.30 wt.%C B 0.43 wt.%C C 0.60 wt.%C D 0.33 wt.%C E None of the above A 0.30 wt.%C Which of the following statements are not true? 1 Si enhances graphitization, and thus increases the tendency of graphite to transform to cementite 2 Cr enhances the chilling tendency in a solidifying cast iron. 3 C Grey cast iron formation is promoted by either a high carbon with the low silicon or a low carbon with high silicon 4 In general, grey cast iron formation is enhanced by slow solidification rate, high Cr content , and low Si 5 Cast irons with carbon equivalent values of 4.3 wt. % are called hypoeutectic irons. 6 Flake graphite cast irons are inoculated to reduce chilling tendency. 7 The gray iron eutectic reaction: Liquid → Austenite + graphite occurs at 1,153०c and carbon equivalent of 4.30 wt. % 8 The L → ૪ + Fe3C eutectic reaction is the metastable reaction that produces ductile cast iron 9 The excellent damping capacity of graphite-based cast iron is independent of the nature and size of the graphite in cast iron. 10 None of the above 1, 4, 5, 8, and 9 As an engineer in a malleable cast iron foundry which of the following would concern you: Increase the molten metal temperature prior to pouring it into the casting mold. Incoming raw material with the composition 2 wt. % Si, 0.8 wt. % Mn, and 0.4 wt. % S. A suggestion by a crew supervisor to inoculate melts 20 minutes before pouring. Suggestion by one of the foundrymen to cast a thin section in a sand mold. Suggestion by an experienced shop floor worker in the foundry to use a high-Cr raw material to cast a thin section in a copper mold. Changing to a new supplier whose raw material is cheaper but has slightly higher carbon and lower Cr (with the same Si level) than your present supplier. Increase the molten metal temperature prior to pouring it into the casting mold. $$$$ Incoming raw material with the composition 2 wt. % Si, 0.8 wt. % Mn, and 0.4 wt. % S. $$$$ Suggestion by one of the foundrymen to cast a thin section in a sand mold. $$$$ Changing to a new supplier whose raw material is cheaper but has slightly higher carbon and lower Cr (with the same Si level) than your present supplier. Amorphous Polymers exhibit which properties? No melting temperature - broad softening temperature, Usually transparent, Low shrinkage, Solvent sensitive, Poor fatigue and wear resistance properties Crystalline Polymers exhibit which properties? sharp melting temperatures, Usually opaque, High shrinkage, Solvent resistive, Goor fatigue and wear resistance properties Which one of the following is the correct definition of ultimate tensile strength, as derived from the results of a tensile test on a metal specimen? A The stress encountered when the stress-strain curve transforms from elastic to plastic behavior. B The maximum load divided by the final area of specimen. C The maximum load divided by the original area of specimen D The stress observed when the specimen finally fails C The maximum load divided by the original area of specimen Which one of the following types of stress-strain relationship best describes the behavior of most metals at room temperature? A Elastic and perfectly plastic B Elastic and strain hardening C Perfectly elastic D None of the above B Elastic and strain hardening The shear strength of metal is usually A Greater than its tensile strength B Less than its tensile strength C None of the above A Greater than its tensile strength The stress at which the maximum force that can be withstood by either a ductile or a brittle material is called the: A Tensile strength B Modulus of elasticity C Yield strength D Breaking strength ATensile strength The slope of stress-strain curve, which is determined primarily by the strength of the atomic bonds within the material, is called the: A Tensile strength B Modulus of elasticity C Yield strength D 0.2% offset yield strength B Modulus of elasticity What does manganese do as an alloy in steels? A combine with sulfur to prevent brittleness and improves hardenability B reduces nodules and enhances corrsion resistance C improves machinability and increases cementite formation D decrease hardenability and increase high temperature properties A combine with sulfur to prevent brittleness and improves hardenability Which of theses are not base physical properties of materials? A volumetric properties B thermal properties C electrical properties D magnetic properties E optical properties F corrosion properties G melting properties F corrosion Which part has the greater stress:(i) a rectangular aluminum bar of 24.6 mm x 30.7 mm cross section, under a load of 7,640 kg; or (ii) a round steel bar whose cross sectional diameter is 12.8 mm under a 5,000 kg load? A The rectangular aluminum bar B The Round steel bar C The stress on both bars is the same B The Round steel bar What is Damping Capacity? The ability to absorb vibrations An age hardening alloy is A A non-heat treatable alloy B A heat treatable alloy C A cast iron D Both heat and non-heat E All F None B A heat treatable alloy The location of the specimen taken in a metallographic study is determined by: A The type of mounting press to be used B The purpose of the metallographic study C The type of etchant to be used D The type of microscope to be used B The purpose of the metallographic study What are the typical etchants used for the macroetching of steel? A A heated 50% conc. HCl solution at 70/80 degrees C for 13-30 minutes B Mixtures of HCl and HNO3 containing some HF C 50% aqueous HNO3 D Keller's reagent and Graff/Sargent A A heated 50% conc. HCl solution at 70/80 degrees C for 13-30 minutes What are the typical etchants used for the microetching of aluminum and its alloys? A 1%, 2%, and 5% of HNO3 in alchohal (Nital) B 2% HF, 25% HNO3, 73% H20 C Keller's reagent and Graff/Sargent D Alcoholic ferric chloride consisting of 5g of FeCl3 C Keller's reagent and Graff/Sargent Which of the following metallic elements is the most abundant on the earth? a. Aluminum b. Copper c. Iron d. Silicon e. None of the above a. Aluminum Which of the cast irons above is/are produced by heat treatment of the cast product? A (i) B (ii) C (iii) D (iv) E (v) F (vi) G None of the above C (iii) and (v) Yea phases A            B             C                  D               E Give the form number and shape Type I - spheroidal graphite