Abstract: A new and useful predictor for maraging stainless steel alloys is created, called the martensite finish temperature, M.sub.f (.degree. F.). This formula enables one to predict the temperature at which a steel is entirely converted to martensite, and is described as M.sub.f =1027--78% Ni--27% Ti--34% Mo. A desirable needle alloy for this amount is nickel at 10%, molybdenum at about 2.7%, and titanium at about 2%.

Abstract: Disclosed are sterile surgical needles formed of alloys of tungsten and a second metal selected from the group consisting of rhenium, rhodium and iridium. The needles exhibit a tensile yield strength in excess of 250,000 psi and a tensile modulus of elasticity in excess of 45.times.10.sup.6 psi, and have advantageously high ductility. The needles have a body portion, a distal point, and a proximal suture mounting portion. Preferably the needles comprise about 3 to about 84 6 weight percent of rhenium, rhodium and/or iridium. The needles exhibit improved yield point and elastic modulus in tension.

Abstract: A surgical needle having an I-beam configuration is disclosed. The surgical needle comprises an elongated member having an I-beam cross section wherein two opposed flange members are connected by a web member. The elongated member has a piercing point extending from its distal end. A cylindrical mounting section extends from the proximal end of the needle for receiving an end of a suture. The needle has increased resistance to bending and buckling when compared to conventional needles and does not have an increase in resistance or drag.