Considering the diffusion welding of the following material combinations, how easy would it be to produce welds in each case? Explain your answer in each case. a. Pure aluminum (AA1100) to aluminum alloy AA6061
b. Ti–6Al–4V to Ti–6Al–6V–2Sn
c. Ni-base Alloy 625 to Alloy 625
d. AISI 304 austenitic stainless steel to AISI 304.

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.