Thaddeus Strusinski
Siemens Energy USA North Carolina Winston-Salem Service Center, USA
Title: Gas turbine blade tip alloy selection for alloy-247LC
Biography
Biography: Thaddeus Strusinski
Abstract
Gas Turbine hot gas path components use highly alloyed Nickle and Cobalt castings (i.e. CM-247, IN-738, IN-939, Rene-80, GTD-111, MGA-1400, ECY-768, MAR-M 509, etc). The alloying elements such as Al, W, C, Ti, & Ta used in these alloys increase the difficulty of achieving good castings and good welds. Siemens has been improving the gas tubine by incorporating ALLOY- 247LC into the blade design. ALLOY-247LC, a gamma prime strengthened nickle based superalloy, has been quite a challenge with which to qualify welding processes. High strength nickle based superalloys can be very expensive to produce into weld fillers. Typically, with minimum lot sizes, these weld filler alloy costs can approach $200,000 USD. And the final mechanical properties studies verifying appropriateness of alloy systems can approach $1,000,000 USD. An upfront selection process is needed to reduce these developmental investments. This presentation uses a Six Sigma Tool to compare and down select 15 potential candidates of weld filler alloys specifically for Alloy-247LC. This is a novel way of looking at the mechanical and physical properties of superalloys from a “survive the weld and post weld heat treatment” strategy. This technique reduces the number of experiments and focuses on the top two down selected weld filler candidates.