Nickel is commonly coated on the outer leads for T8 metal package. The leadselectrodeposited by conventional dull or bright nickel over 5μm at direct current from Watt bathare hard to pass the bend fatigue test for t...Nickel is commonly coated on the outer leads for T8 metal package. The leadselectrodeposited by conventional dull or bright nickel over 5μm at direct current from Watt bathare hard to pass the bend fatigue test for three times. Nickel electrodeposited at multi waveformcurrent including direct current, single and double pulse from sulfamate bath can improve the bendfatigue strength of leads. Such nickel plating has a multilayer structure, its morphology ofsublayers can be clearly seen in its cross section with SEM. The electrochemical study shows thatthese sublayers have different corrosion potentials. The bend fatigue test of leads with suchplating for T8 metal package shows that the number of bend increases with the decrease of averagecurrent density of multi waveform, which can be attributed to the reduction of every sublayerthickness and the increase of layer numbers under the same condition of total thickness.展开更多
Carburized steel grades are widely used in applications where high surface near hardness is required in combination with good core toughness as well as high strength and fatigue resistance. The process of carburizing ...Carburized steel grades are widely used in applications where high surface near hardness is required in combination with good core toughness as well as high strength and fatigue resistance. The process of carburizing lower to medium carbon containing steel can generally provide this combination of properties and has been prac- ticed for several decades. Such steel is essential in the vehicle power-train, machines and power generation equipment. However, the increasing performance demands by such applications as well as economical considerations forced steel producers to develop better alloys and fabri- cators to design more efficient manufacturing processes. The present paper describes recent concepts for alloy design optimization of carburizing steel and demonstrates the forthcoming beneficial consequences with regard to manufacturing processes and final properties.展开更多
文摘Nickel is commonly coated on the outer leads for T8 metal package. The leadselectrodeposited by conventional dull or bright nickel over 5μm at direct current from Watt bathare hard to pass the bend fatigue test for three times. Nickel electrodeposited at multi waveformcurrent including direct current, single and double pulse from sulfamate bath can improve the bendfatigue strength of leads. Such nickel plating has a multilayer structure, its morphology ofsublayers can be clearly seen in its cross section with SEM. The electrochemical study shows thatthese sublayers have different corrosion potentials. The bend fatigue test of leads with suchplating for T8 metal package shows that the number of bend increases with the decrease of averagecurrent density of multi waveform, which can be attributed to the reduction of every sublayerthickness and the increase of layer numbers under the same condition of total thickness.
文摘Carburized steel grades are widely used in applications where high surface near hardness is required in combination with good core toughness as well as high strength and fatigue resistance. The process of carburizing lower to medium carbon containing steel can generally provide this combination of properties and has been prac- ticed for several decades. Such steel is essential in the vehicle power-train, machines and power generation equipment. However, the increasing performance demands by such applications as well as economical considerations forced steel producers to develop better alloys and fabri- cators to design more efficient manufacturing processes. The present paper describes recent concepts for alloy design optimization of carburizing steel and demonstrates the forthcoming beneficial consequences with regard to manufacturing processes and final properties.
