《材料科学与工程基础》英文习题及思考题及答案,本人从网上狂搜,兄弟们姐妹们狂下啊,不要辜负我的劳动啊!!!!

3 , respectively.

8.53 In terms of molecular structure, explain why phenol-formaldehyde (Bakelite)

will not be an elastomer.

10.50 Compute the mass fractions of αferrite and cementite in pearlite. assuming

that pressure is held constant.

10.52 (a) What is the distinction between hypoeutectoid and hypereutectoid steels?

(b) In a hypoeutectoid steel, both eutectoid and proeutectoid ferrite exist. Explain the difference between them. What will be the carbon concentration in each? 10.56 Consider 1.0 kg of austenite containing 1.15 wt% C, cooled to below 727_C

(a) What is the proeutectoid phase?

(b) How many kilograms each of total ferrite and cementite form?

(c) How many kilograms each of pearlite and the proeutectoid phase form? (d) Schematically sketch and label the resulting microstructure.

10.60 The mass fractions of total ferrite and total cementite in an iron–carbon alloy

are 0.88 and 0.12, respectively. Is this a hypoeutectoid or hypereutectoid alloy? Why?

10.64 Is it possible to have an iron–carbon alloy for which the mass fractions of total

ferrite and proeutectoid cementite are 0.846 and 0.049, respectively? Why or why not?

第四章习题和思考题

7.3 A specimen of aluminum having a rectangular cross section 10 mm _ 12.7 mm

is pulled in tension with 35,500 N force, producing only elastic deformation.

7.5 A steel bar 100 mm long and having a square cross section 20 mm on an edge is

pulled in tension with a load of 89,000 N , and experiences an elongation of 0.10 mm . Assuming that the deformation is entirely elastic, calculate the elastic modulus of the steel.

7.7 For a bronze alloy, the stress at which plastic deformation begins is 275 MPa ,

and the modulus of elasticity is 115 Gpa .

(a) What is the maximum load that may be applied to a specimen with a

cross-sectional area of 325mm, without plastic deformation?

(b) If the original specimen length is 115 mm , what is the maximum length to which it may be stretched without causing plastic deformation?

7.8 A cylindrical rod of copper (E _ 110 GPa, Stress (MPa) ) having a yield strength

of 240Mpa is to be subjected to a load of 6660 N. If the length of the rod is 380 mm, what must be the diameter to allow an elongation of 0.50 mm?

7.9 Consider a cylindrical specimen of a steel alloy (Figure 7.33) 10mm in diameter

and 75 mm long that is pulled in tension. Determine its elongation when a load of 23,500 N is applied.