Product Code: JLA_8_3_161

Authors:
R. J. Hull
M. L. Lander

Since 1976, the Laser Hardened Materials Evaluation Laboratory (LHMEL) has been characterizing material responses to laser energy in support of national defense programs and the aerospace industry. Now that capability is available to commercial industry as well. LHMEL's power levels, beam uniformity, and diagnostics capabilities make it an ideal facility for proof‐of‐concept testing or process development. Located at Wright‐Patterson Air Force Base, Ohio, LHMEL is managed by the Wright Laboratory Materials Directorate and operated by Lawrence Associates, Incorporated. The facility's advanced hardware is centered around two laser systems: the LHMEL I laser, producing 15 kW of continuous‐wave (CW) power on target; and LHMEL II, producing 150 kW of CW power on target. Both lasers operate at 10.6 μm and can deliver stable, full‐power irradiations for durations up to 80 s. Both LHMEL devices use a multimode resonator configuration producing a flat‐top spatial intensity distribution. This beam profile delivers a uniform amount of energy over the entire beam diameter and ensures a controlled and repeatable laser exposure on target. The singular capabilities of the LHMEL facility provide unique opportunities for commercial materials processing. Uses of LHMEL might include demonstration of the feasibility of a new materials processing technique before investing capital in its development; simulating the high service life temperatures experienced by parts within an automobile or jet engine; performing a limited production run to laser cut thick steel plates for a special custom order; or using LHMEL's high power to perform deep‐penetration welds of steel, aluminum, or titanium. LHMEL has already performed extensive work in the area of thermal load simulation and has begun initial testing efforts in other areas of materials processing. LHMEL's capabilities are perhaps most beneficial in the surface treatment of materials. Applications requiring uniform irradiation of large surface areas to produce the ideal heat treatment with limited or single passes could be satisfied by LHMEL. Initial heat treatment tests have been performed at LHMEL. Other techniques to increase wear resistance, extend service life, or even inhibit surface corrosion might be developed using LHMEL. Tests are performed on a cost‐reimbursement basis or, if appropriate, a Cooperative Research and Development Agreement (CRDA) can be negotiated.