Scanning Temperature Measurement System (STeMS) for Real-Time Process Monitoring During Laser Additive Manufacturing of Metallic Structural Materials
Abstract
Laser additive manufacturing (LAM) for structural materials using a powder fusion process based on selective laser melting (SLM) is suffering from inconsistent build. In-situ powder fusion process control, for instance control of laser power, is therefore desirable to mitigate the impact of variations in build environment, powder condition and powder size distribution, etc. Process control could be based on the assessment of heating and cooling rates or temperature gradients at the powder and solidified surfaces during the SLM process. The University of Dayton proposes the development of a scanning temperature measurement system (STeMS) for laser additive manufacturing that allows for measurement of spatio-temporal temperature distributions in and around the melting pool. The temperature sensing system will be based on scanning the surface in the vicinity of the melting pool using thermal radiation emitted by the heated metal and coupled into an array of receiver fibers by an imaging lens so that each fiber tip position is an optical conjugate to a spot on the metal surface. The receiver fibers are attached to a piezoelectric actuator that provides an oscillating lateral fiber tip position, which corresponds to scanning of the temperature measurement spot across the surface. This approach is a compromise between a highresolution thermal imaging system, which is typically too slow for process control applications, on one hand, and single-detector pyrometry, which can provide high-speed but spatially unresolved temperature measurements, on the other hand.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 24, 2019
- Source ID
- N000141912110
Entities
People
- Thomas Weyrauch
Organizations
- Office of Naval Research
- United States Navy
- University of Dayton