58851 - Weldability and Properties of a Newly Developed Lw4280 High Gamma Prime Nickel Based Superalloy for 3d Am and Repair of Turbine Engine Components 

WELDABILITY AND PROPERTIES OF A NEWLY DEVELOPED LW4280 HIGH GAMMA PRIME NICKEL BASED SUPERALLOY FOR 3D AM AND REPAIR OF TURBINE ENGINE COMPONENTS

Alexandre B. Gontcharov and Paul Lowden

Liburdi turbine Services Inc, 400 Hwy 6 North, Dundas, ON, Canada

Ashutosh Jena, Sunyong Kwon, and Mathieu Brochu

McGill University, Materials Engineering Department, 3610 University Street, QC, Canada

ABSTRACT

Chemical composition, structure, mechanical and oxidation properties of welds produced utilizing laser direct energy deposition process (LDED) of a newly developed LW4280 welding powder will be presented. Crack-free and high-density specimens were fabricated by multi-pass powder LDED to manufacture standard and subsized tensile test samples as per ASTM E-8.  Optical (OM) and scanning electron microscopy (SEM) reveled the formation of epitaxial grain growth during solidification of the welding pool followed by precipitation of fine gamma prime (γ’) phase during the reheating from the subsequent weld layers.  A   sub-solvus primary aging determined using Thermo-Calc software followed by secondary aging resulted in precipitation of above 49% of cuboidal γ' phase.  Excellent ultimate tensile strength (UTS) of 190 KSI (1310 MPa), 0.2% yield strength (0.2%YS) of 124 KSI (855 MPa) and elongation (δ) of 18.7% were measured at ambient temperature. At 1700°F (926°C), the tensile testing yielded UTS of 84 KSI (579 MPa), 0.2%YS of 67 KSI (462 MPa), and δ of 18.8%. Cyclic oxidation resistance of the LW4280 welds at 2048°F (1120°C) was superior to Rene 80, similar to Mar M247 while slightly below Rene 142.