CWB MOD 22 Welding Metallurgy of Stainless Steels Questions with Verified Answers

CWB MOD 22 Welding Metallurgy of Stainless Steels Questions with Verified Answers Exercise Questions Section 1 - 6 1. Complete the following : a) Chromium stabilizes the _________form of iron b) Nickel stabilizes the ______________form of iron a) BCC b) FCC Exercise Questions Section 1 - 6 2. If a straight chromium steel of 18% Cr and < 0.1% C is heated to 1000 Celsius will it transform to austenite or remain as ferrite? Remain as ferrite Exercise Questions Section 1 - 6 3. What is the predominant structure of an 18 % Cr, 8% Ni steel at room temperature? austenite Exercise Questions Section 1 - 6 4. The chromium content of a stainless steel is 20%. Is it likely this is a martensite grade? no Exercise Questions Section 1 - 6 5. What does the Letter L signify in the designation 316L? a) low chromium b) longitudinal specimen c) low carbon (maximum 0.03%) c) low carbon (maximum 0.03%) Exercise Questions Section 6-7 1. A 14% Cr martensitic steel hardened to 1000 Celsius and air cooled produces: a) ferrite b) austenite c) martensite c) martensite Exercise Questions Section 6-7 2. Determine the minimum specified titanium content of a type 409 ferritic stainless steel with 0.05% carbon 0.3% Ti Exercise Questions Section 6-7 3. Does an austenitic stainless steel have a greater or lesser work hardening rate than carbon steel? Greater Exercise Questions Section 6-7 4. True or False 100 % CO2, is not generally used for GMAW of stainless steels True Exercise Questions Section 8 1. The loss of corrosion resistance due to carbide formation and chromium depletion is known as: a) sigma formation b) sensitization c) stabilization b) sensitization Exercise Questions Section 8 2. What maximum carbon level is usually specified to ensure freedom from sensitization during welding? a) 0.03% b) 0.003% c) 0.3% a) 0.03% Exercise Questions Section 8 3. The presence of residual delta ferrite in the weld metal indicates that primary solidification was: a) ferrite b) austenite a) ferrite Exercise Questions Section 8 4. A method of controlling weld metal fissuring is to: a) always use a stabilized weld metal b) ensure primary solidification is austenite c) ensure there is a small amount of residual delta ferrite in the weld metal c) ensure there is a small amount of residual delta ferrite in the weld metal Exercise Questions Section 9 1. For the following weld metal (E312) draw a box on the Schaeffler diagram showing the possible range of structures: