155. Which is false statement about properties of aluminium
A.Modulus of elasticity is fairly low
B.Wear resistance is very good
C.Fatigue strength is not high
D.Creep strength limits its use to fairly low temperatures

---

156. Addition of copper to aluminium results in
A.Improvement of casting characteristics
B.Improvement of corrosion resistance
C.One of the best known age and precipitation-hardening systems
D.Improving machinability

---

157. Addition of manganese to aluminium results in
A.Improvement of casting characteristics
B.Improvement of corrosion resistance
C.One of the best known age and precipitation-hardening systems
D.Improving machinability

---

158. Elinvar, an alloy used in precision instruments, hair springs for watches, etc. contains the following element as principal alloying element
A.Iron
B.Nickel
C.Aluminium
D.Zinc

---

159. Which of the following alloys does not have copper as one of the constituents
A.Delta metal
B.Monel metal
C.Constantan
D.Nichrome

---

160. Addition of lead and bismuth to aluminium results in
A.Improvement of casting characteristics
B.Improvement of corrosion resistance
C.One of the best known age and precipitation-hardening systems
D.Improving machinability

---

161. Addition of silicon to aluminium results in
A.Improvement of casting characteristics
B.Improvement of corrosion resistance
C.One of the best known age and precipitation-hardening systems
D.Improving machinability

---