Can DC argon arc welding machine weld nickel alloy?

Of course.

According to Baidu Encyclopedia, DC argon arc welding is suitable for welding stainless steel, low alloy steel, low carbon steel, medium carbon steel, high carbon steel and nickel alloy, as well as copper, copper alloy, titanium alloy and other metals.

Features of DC argon arc welding machine: advanced inverter technology, high working frequency, small size, light weight and easy to carry.