Talk:Deterioration Armor Piercing Shell/@comment-2600:1702:4A0:3620:8186:25A9:D0D:2A14-20181123125710

This is actually a bit of joke by the devs.

劣化 is TL'd here as deterioration or deteriorated. It's short for 劣化ウラン as in "deteriorated uranium" or "depleted uranium."

徹甲弾 = Armor Piercing Shell.

So it's a DP penetrator shell, like the ones modern tanks use.