PARTNERS: Purdue University, Connecticut Center for Advanced Technology (CCAT)

PROBLEM STATEMENT: Dirty white spot (DWS) defects in forged IN718 turbine parts pose a significant safety risk to the aviation, marine, and power generation industries. Despite the manufacturing process being specifically designed to minimize these defects, engine failures still occur due to DWSs. IN718 turbine parts for turbine engines are produced using a triple melting process which requires substantial energy, time, and cost. Improving this process can have significant energy implications across multiple industries.

PROJECT GOAL: The goal of the proposed program is to develop a simulation/testing framework to determine the feasibility of using ultrasound to mitigate DWSs in the VAR process. If it can be shown that this method effectively reduces the frequency of DWSs, IN718 parts can be double melted as opposed to requiring triple melting.

TECHNICAL APPROACH: The proposed program entails 1) Multiscale solidification models to quantify the effect of ultrasound on crown formation; 2) Crown vibration, fracture, and melting models for ultrasonic feature optimization to mitigate risk of fall-in particles to DWS formation; 3) Specimen design, manufacturing, and experimental testing for model development, calibration, and validation.


Task 1: Phase 1 Program Management
Task 2: Microscale Solidification/Melting Droplet Model
Task 3: Ultrasonic Melt/Solidification Additive Manufacturing Tests
Task 4: Model Calibration and Validation
Task 5: Transient 3D Macroscopic VAR Model
Task 6: Multiscale Coupled VAR Ultrasonic Vibration Model
Task 7: Phase 2 Program Management
Task 8: Transient VAR Model with Particle Tracking
Task 9: Microscale Transient Fall-in Particle Model
Task 10: Resonance and Vibration Fracture Model
Task 11: Crown Specimens Testing and Fabrication

POTENTIAL IMPACT: Eliminating the requirement for a third melting step for IN718 turbine parts used in aviation, marine, and energy generation applications will result in >30% energy savings over the current practice.

  • Considering only turbofan engines, the total energy saved is ~264 GWh, equivalent to the annual energy consumption of >25,000 US homes
  • Including all turbine engines (power generation, turboprop, and marine), the total annual energy savings is ~600 GWh, equivalent to >57,000 US homes

BENEFITS: The proposed program will contribute to advancing the CESMII goals and objectives through the following performance metrics:

  • Energy Productivity
  • Energy Efficiency
  • Industry Deployment Costs; and 4. Workforce. 
Member % Cost Share CESMII % Cost Share Duration
50% 50% 18 Months


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