News and Events

Meeting: Materials Science & Technology 2011               Symposium: Additive Manufacturing of Metals

Oral Presentation  "Control and Monitoring of Laser Deposition Processes

Presented by Richard Grylls, Optomec Inc.  9:00 am - D130

David Keicher of Optomec, Inc., James E Craig of Stratonics, Inc.

Abstract: The first Laser Engineered Net Shaping (LENS^®) metal additive manufacturing system was installed thirteen years ago at The Ohio State University. That first system relied entirely on the skill of the operator to ensure a successful deposition - no automated controls were available at that time. Since then, laser deposition technology has become an established industrial process, and the requirements for process control have been better defined. In this presentation we will discuss when process control is needed, how it can be achieved, and the future directions in this area. Particular attention will be paid to temperature measurement, melt pool size, toolpath generation, and atmosphere control.

Oral Presentation  "Initial Developments in Monitoring and Modeling of Laser Additive Manufacturing with Titanium"

Presented by James E Craig, Stratonics, Inc.  10:00 am - D130

Thomas Wakeman of Stratonics, Inc., Richard Grylls of Optomec, Inc., Shawn Kelly of Penn State Univ.

Abstract: We will describe a set of experiments using LENS to deposit Titanium and model developments to analyze the thermal and metallurgical evolution of the deposit. Deposits were built using a range of laser powers to examine how metallurgy varied with thermal characteristics. A two-wavelength imaging pyrometer was used to monitor the melt pool thermal characteristics and a single wavelength imaging pyrometer was used to monitor the thermal characteristics of the side of the deposit. The peak temperature, dimensions and heating/cooling rate of the melt pool was measured for each scan and throughout the deposit. The temperature gradients down the side of the deposit were also measured. A layered thermal model was used to estimate internal temperatures and to provide a link to the resultant metallurgy.

ThermaViz^® Exhibited & Technical Paper  Presented at TMS Annual Meeting, San Diego, CA Mar. 3, 2011

TECHNICAL PRESENTATION  On-line Imaging Pyrometer for Laser Deposition Processing

James E Craig, Thomas Wakeman of Stratonics, Inc., Richard Grylls, James Bullen of Optomec, Inc.

Abstract: An online imaging pyrometer has been developed to monitor the temperature distribution of the melt pool in laser additive manufacturing processes. The imaging pyrometer uses two CCD cameras with “long and short” wavelength filters in the NIR waveband. The intensity ratio is formed and the two wavelength temperature is determined from a calibration, relating the ratio to the temperature. In the experiment, deposit strips are formed over a variation of laser power levels, ranging from standard levels for a superalloy to about half the initial level. As the power is lowered, the deposit efficiency is reduced, as is its dimensions. Melt pool temperature distributions are measured in the final 6 through 10 passes and their properties will be presented and described. Peak temperatures of about 1800°C are noted for standard power levels, and in general lower temperatures are observed at lower power levels.

ThermaViz^® Exhibited at LAM Workshop, Houston Texas, Feb. 16-17, 2011

Stratonics ThermaViz^® Sensor provides fully integrated thermal imaging on Optomec's LENS^® powder-metal fabrication system.

Stratonics, Inc. plans two exhibitions with Optomec, Inc. Stratonics will feature their Surface ThermaViz^®, an innovative optical pyrometer which incorporates sophisticated image acquisition and analysis software to provide real-time, true temperature images and measurements.

Optomec is the world-leading provider of additive manufacturing solutions for high performance applications in the Electronics, Solar, Medical, and Aerospace & Defense markets. These systems utilize Optomec’s patented Aerosol Jet^® Printed Electronics technology and LENS^® powder-metal fabrication technology. The company has a global customer base of more than 100 users that includes many industry-leading manufacturers and Universities.  http://optomec.com/     (LENS^® is a registered trademark of Sandia Corporation)

Click on the button to view features and specifications in a PDF file.        

Stratonics wins Phase I SBIR contract to develop a Multi-view Sensor Suite/Process Model-based Control System for direct digital manufacturing (DDM)

The Office of Naval Research has awarded Stratonics a Phase I SBIR to demonstrate the feasibility of measuring critical variable parameters and controlling thermal conditions in direct digital manufacturing (DDM) by developing a multi-sensor/process model-based control system. The innovation combines a multi-view thermal imaging sensor suite, finite element method (FEM) model and real-time software algorithms to control the laser power, deposition position, and powder feed of laser material deposition processes. Stratonics successful development of DDM thermal control will prevent defects/flaws (voids, lack of fusion, porosity because of too cold a process) or inhomogeneous deposits (chemical variation due to excessive melting or vaporization, and variation of microstructure within a part). DDM System variable parameters will be controlled to produce the required changes in the process to achieve desirable deposit metallurgy. Stratonics has formed a strong team of experts, including Pennsylvania and Ohio State Universities and industrial partners, Optomec, Pratt & Whitney and Morris Technologies, all leaders in additive manufacturing technologies.