A297 HL

Grade HL is a specialized heat-resistant stainless steel casting alloy specified by ASTM A297/A297M, developed for high-temperature applications requiring enhanced structural integrity and resistance to oxidation. With elevated levels of chromium and nickel—typically higher than standard HK or HH grades—HL offers improved creep strength and long-term dimensional stability under severe thermal conditions. This alloy is commonly used in critical furnace components, reformer tubes, and heat-treat fixtures subjected to sustained elevated temperatures. Grade HL is chosen for applications in petrochemical and metallurgical industries where maximum performance and reliability are essential under continuous high-heat service.