Top 1000+ Solved Material Science MCQ Questions Answer
Q. In Cu alloys season cracking is a type of
a. crevice corrosion
b. stress corrosion cracking
c. intergranular corrosion
d. erosion corrosion
Q. H2O + (1/2) O2 + 2e-1 --> 2OH-(Reduction) is reaction taking plcae at ---
a. cathode
b. anode
c. both a and b
d. none of the above
Q. in dissolved oxygen content of electrolyte has effect on corrosion reaction
a. it forces the cathodic reaction to the right i.e. producing more oh- ions
b. it removes more electrons and therefore accelarate the corrosion at the anode
c. both are true sentenses
d. none of the above is right
Q. in oxygen absorption reaction mechnism os corroison
a. cathode usually have large areas than anode
b. anode usually have large areas than cathode
c. anodes and cathodes are same
d. none of the above is right
Q. scratches, local straining of metal due to non- uniform stresses, sliding uncer load leads to
a. pitting corrosion
b. stress corrosion cracking
c. intergranular corrosion
d. erosion corrosion
Q. out of the following sentences which sentence is not true for pitting corrosion ?
a. brake in protective caotings
b. destruction of passive layer
c. insufficient use of anodic inibitor
d. none uniform heat treatment
Q. in intergranular corrosion
a. grain acts as cathode
b. gb acts as cathode
c. gb acts as anode
d. both a and c
Q. in stainless steel the precipitation of Cr carbides leads to
a. pitting corrosion
b. stress corrosion cracking
c. intergranular corrosion
d. erosion corrosion
Q. sensitized stainless steel are
a. prone to corroiosn
b. protected against corrosion
c. not related with corrosion
d. none of the above
Q. sensitized stainless steel means
a. group of steel prone to corrosion in welding in the range of 500to 800 oc
b. group of steel prone to corrosion in welding below 500 oc
c. group of steel prone to corrosion in welding above 800 oc
d. none of the above
Q. the type of corrosion which is produced by con=mbined effect of mechanical stress and a corrosive environment on metal is called as
a. pitting corrosion
b. stress corrosion cracking
c. intergranular corrosion
d. erosion corrosion
Q. in stress corrosion cracking
a. only internal stresses are
b. only extrenal stresses are
c. only residual stres are
d. all of the above
Q. the critical level of stress depends uopn factor
a. composition of alloy
b. grain size, microstructur e and geometry of the component
c. surface finish of the component
d. all of the above
Q. the critical level of stress depends uopn factor
a. composition of alloy
b. type of environmnet
c. service temperatue
d. all of the above
Q. carbon steels crack in nitrate solutions is a type of
a. pitting corrosion
b. stress corrosion cracking
c. intergranular corrosion
d. erosion corrosion