DID YOU KNOW? DTIC has over 3.5 million final reports on DoD funded research, development, test, and evaluation activities available to our registered users. Click HERE
to register or log in.
Spur Gear Laser Surface Hardening MM/T Program
Final rept. Mar 1979-May 1981
BELL HELICOPTER TEXTRON INC FORT WORTH TX
Pagination or Media Count:
The purpose of this program was to surface harden spur gear specimens using laser and compare their tooth pitting life and tooth bending strength with that of carburized AMS 6265 gears. The intent was to replace aircraft quality accessory drive carburized AMS 6265 gears with laser hardened gears and achieve significant cost savings. Preliminary work was conducted using 300M. Subsequently, 300M was replaced with D6AC because it failed to meet the requirement of Rc 60 minimum surface hardness after a 300 temper. Laser exposure curves were developed for both 300M and D6AC using flat disc type specimens. A unique system for splitting a laser beam into four beams and integrating the individual beams and directing these at the root and adjoining tooth flanks of a tooth gap was developed. The main problems encountered were tempering of a previously hardened tooth flank, incomplete coverage from end face to end face and laser power and spatial drifts. The report presents a detailed description of the multi-beam laser heat treating station, metallurgical properties of D6AC, findings of the laser heat treating experiments, conclusions and recommendations for overcoming problems encountered.
APPROVED FOR PUBLIC RELEASE