Question

11. (a) Describe the challenges in obtaining dissimilar weld joints of e.g. stainless steel and [5 marks] titanium (b) From the phase diagram shown in Figure 4, what are the typical intermetallic phase(s) that will form during fusion welding of steel and titanium, and what are their typical chemical compositions? [3 marks] 1700 1670 Liquid (L) 1536 1500 LFe2Ti 7° L+FezTi L+aFe 1317 1300bcc (aFe10 12 89 27.6 35-2 49-7 L+ BTi 16 L+FeTi 1085 525 1100 bcc (ATi) Fe2TiFeTi aFe Fe2Ti 900 BTi FeTi 882 BTi+ aTi FeZTi (A) Fe Ti- 700 590 FeTi (aTi) 500l Fe 10 20 30 40 50 70 Ti 60 80 90 Atomic Percent Titanium Fig.4 Phase diagram of Fe-Ti. Temperature,c

Answer 1

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