... that can avoid diamond oxidation and degradation. Electroplated diamond core bits obtain much faster penetration than impregnated diamond core bits in drilling ... drilling different rock formations, the matrix hardness of electroplated diamond core bit could be different, please refer to "Matrix Selection ... TNW ,ATW, BTW ,NXD3, AX, NXC, AXT, NX ,T6H 4 9/6, NWD4 412F, SK6L146 ,TT46 ,TB56 ,TS116 ,CHD101 ...