End effector scissor elements for laparoscopic surgical instruments are provided in the form of investment case cobalt base alloy elements. The cobalt base alloy scissor elements are homogeneous in composition. Each element has in its as-cast form an elongate portion having an integral cutting edge. At least on of the scissor elements also has a through-hole transverse to the elongate portion. The scissor elements are arranged as scissor cutting instruments by opposing their cutting edges, and by engaging the through-hole of each pivoting element with apparatus coupled to an actuating push-rod of the laparoscopic surgical instrument. The preferred cobalt base alloy is a cobalt base superalloy with at least 38% cobalt, and preferably 50% or more cobalt. The cobalt base alloy should be sufficiently hard to scratch stainless steel.