Abstract: A precipitation strengthening type nickel base single crystal alloy, which consists essentially of, on a weight percent basis,10-30% chromium,0.1-5% niobium,0.1-8% titanium,0.1-8% aluminum,optionally one or more components selected from the group consisting of 0.1-3% tantalum, 0.05-0.5% copper, 0.05-3% hafnium, 0.05-3% rhenium, 0.05-3% molybdenum, 0.05-3% tungsten, 0.05-0.5% boron, 0.05-0.5% zirconium, andthe remainder being nickel and incidental impurities, and exhibits a narrow solidification temperature range.

Abstract: A combination of a plug assembly to be attached to a printed wiring board, and a receptacle assembly to be attached to a shelf back-board. The plug assembly comprises a set of plug contacts mounted to a plug housing. The receptacle assembly comprises a receptacle housing capable of mating engagement with the plug housing, and a set of resilient, bladelike receptacle contacts mounted to the receptacle housing. Each bladelike receptacle contact has two protuberances formed in longitudinally spaced positions thereon. Each receptacle contact is so made that only one of the two protuberances thereon is normally held against one associated plug contact upon interfitting engagement of the receptacle housing with the plug housing. At least selected one of the receptacle contacts butts on a projection on the receptacle housing and is thereby resiliently displaced in such a direction that the two protuberances on the displaced receptacle contact are both held against one associated plug contact.