Assignment No. 5 1. Increase of diffusion bonding temperature a. Increases bonding time b. Reduces the diffusion rate c. Decreases the metallic intimacy during initial stage d. Reduces the voids the interface Correct Answer- d. Reduces the voids the interface 2. Interlayer materials for Diffusion bonding should not have a. Low melting point b. High ductility c. Low yield strength d. Metallurgical compatibility with mating components Correct Answer- a. Low Melting Point 3. Energy requirement for ultrasonic welding is not influenced by a. Hardness b. Thickness c. Melting point d. Surface condition Correct Answer- c. Melting Point 4. Elastic plastic deformation in ultrasonic welding is caused by a. Compressive stress b. Shear stress c. Combination of compressive and shear stresses d. Torsional stress Correct Answer- c. Combination of compressive and shear stresses 5. Weld bonding procedure does not use a. Curing b. Adhesive c. Spot welding d. Filler metal Correct Answer- d. Filler Metal 6. Strength of weld-bond is influenced by a. Filler b. Electrode strength c. Arc voltage d. Nugget diameter Correct Answer- d. Nugget Diameter 7. Surface preparation and pre-treatment of surfaces for adhesive joining helps to a. Reducing stress concentration b. Reduce pressure required c. Better curing d. Better wetting and distribution of adhesive Correct Answer- d. Better wetting and distribution of adhesive 8. Mechanism which does not affect the strength of adhesive joint a. Mechanical interlocking b. Metallurgical bonding c. Electrostatic force d. Chemical bonding Correct Answer- b. Metallurgical bonding 9. Solid state joining can cause problem of a. Partial melting zone b. Porosity c. Softening of HAZ d. Crater cracks Correct Answer- c. Softening of HAZ 10. Solid stage joining process which does not use external heating a. Diffusion bonding b. Magnetic pulse welding c. Spot welding d. Flash butt welding Correct Answer- b. Magnetic Pulse Welding .