225. Maximum hardenability of steel depends upon its
A. Chemical composition
B. Carbon content
C. Grain size
D. Alloying elements content
✅ The correct answer is option D.
228. Dephosphorisation of molten pig iron is favoured by
A. Oxidising and basic slag
B. Reducing and basic slag
C. High activity co-efficient of phosphorous in metal
D. Oxidising and neutral slag
✅ The correct answer is option B.
191. __________ is used for tying the steel coloumns to concrete foundation.
A. Grouting
B. Eyebolt
C. Anchor bolts
D. Refractory castables
✅ The correct answer is option C.
194. In TIG welding, thoriated tungsten electrodes are used, because it
A. Has higher current carraying capacity
B. Has better electron emissivity
C. Is stronger than ordinary tungsten
D. Is easy to prepare
✅ The correct answer is option B.
197. The diffusion co-efficient of Ni in Cu at 1000 K is 1.93 x 10⁻¹6⁶ m² . S⁻¹ and it is 1.94 x 10⁻¹⁴ m² S⁻¹ at 1200 K. The activation energy (in k. J.mole⁻¹ ) for the diffusion of Ni in Cu is
A. 130
B. 180
C. 230
D. 250
✅ The correct answer is option C.
200. Cementite is in the lamellar form in the __________ phase of steel.
A. Martensitic
B. Bainitic
C. Pearlitic
D. Ferritic
✅ The correct answer is option C.
203. __________ addition increases the depth of hardness of steel.
A. Chromium
B. Nickel
C. Tungsten
D. Vanadium
✅ The correct answer is option A.
206. Springs are not made of
A. Phospher bronze
B. Nickel steel
C. Monel
D. Carbon steel (c ≤ 0.5%)
✅ The correct answer is option D.
209. Wrought iron is not
A. Uctile & resistant to corrosion/rusting
B. Weldable easily
C. Having uniform strength in all directions
D. Having maximum tensile strength along the lines of slag distribution
✅ The correct answer is option C.
211. In a fuel cell, chemical energy is converted into
A. Electrical energy directly
B. Mechanical energy
C. Electrical energy and stored therein
D. None of these
✅ The correct answer is option A.