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[MW:12956] Cracking problem during Hardfacing (FCAW)

By Materials & Welding
Hello Friends,
 
We are conducting trials for Tungsten carbide Hardfacing on F-22 material (2.1/4Cr - 1 Mo). we are facing problem of transverse hairline cracks on weldbead. need your help to overcome this problem.
Process: FCAW
Filler wire Dia: 1.2mm
Cuerrent used: during trial we changed current from 87Amps to 140Amps. different runs were taken but all cracked
Volts: 16 to 19.5V
Wire feed: 2.8 to 5m/min
Travel speed: 235 to 600mm/min
Preheat: 120 to 260DegC
Shielding: Argon
 
With these parameters, we achieved satisfactory weld bead appearance though.
 
Please let me know if i am missing any factor which is vital for the success of the process. also need you guidance on the parameters i tried.Hope to see your suggestions soon
 
Please let me know if anyother info is needed.
 
Thank you.
 
Regards,
Ajay

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