Alloy K500 is a nickel-copper alloy, we can compare it with Alloy 400, but this is a precipitation hardenable alloy because of aluminium and titanium content.                                                            
Alloy K-500 keeps excellent corrosion resistant characteristics as Alloy 400 and  has higher strength and hardness after precipitation hardening. Alloy K500 is non-magnetic, when welded this alloy should be annealed and stress relieved before aging.