556 TM alloy provided all three of these requirements for a major aircraft producer. They had experienced excessive cracking necessitating frequent weld repair of 316 stainless steel salt pot boxes.
Maintenance costs are down and reliability is increased.
X alloy baskets, also show below had given years service carburizing automotive transmission gears when the photo was taken. Baskets made of a competitive alloy had to be replaced on an average of once a year. Even though X alloy cost roughly twice as much as the competitive alloy, it became cost effective the first year of service. Alloy X carburizing basket. After 14 months of intensive field testing, HR-120 alloy was selected over RA 333 alloy.