Alloy development can range from purely empirical, trial-and-error efforts to very theoretical, based on either fundamental first-principles calculations or computational-modeling using various kinds of data base inputs. However, “real-world” efforts to improve or optimize complex engineering alloys often cannot afford the time or cost of either extreme approach. in the past 10-15 years, an alloy development and processing optimization methodology has been developed that utilizes strategic microanalytical data (both detailed microstucture and microcompositional information) as the critical input that then enables efficient and effective design of various kinds of alloys for improved high-temperature performance [1-6]. in many cases, first time tests produce outstanding high-temperature creep or creep-rupture results, and enable improvements without trading off one property for another. This invited paper will highlight several examples of significantly improved creep resistance obtained using such microstructural design.

This microstructural design methodology for high-temperature creep-resistance was initially developed for and demonstrated in austenitic stainless steels (Fe-14Cr-16Ni) designed for improved creep-strength and rupture resistance at 700°C and above for superheater and boiler tubing in advanced fossil power plants.