Ablation-Resistant High-Density Hypervelocity Projectile Nosetip
Navy SBIR FY2013.1

Sol No.: Navy SBIR FY2013.1
Topic No.: N131-071
Topic Title: Ablation-Resistant High-Density Hypervelocity Projectile Nosetip
Proposal No.: N131-071-0460
Firm: St. Croix Research
5535 Fern Dr.
San Jose, California 95124-6311
Contact: Charles Powars
Phone: (408) 723-1216
Web Site: stcroixresearch.com
Abstract: This project will develop and demonstrate a high-temperature ceramic-coated tungsten nosetip for hypervelocity projectiles. The ceramic coating will delay oxidation, which causes increased surface roughness, boundary layer transition, much higher heat transfer rates, and substantial ablation of tungsten and carbon-carbon materials. If laminar flow over the nosetip can be maintained, tungsten's properties enable it to heat-sink the incident aerodynamic heating and avoid ablation for the Mach 8 launch condition of interest. Development of the ceramic material and coating process will build on our prior ceramic-coated tungsten experience. Phase I will include fabrication and characterization of oxidation-resistant ceramic coated tungsten nosetip specimens.
Benefits: Benefits of the proposed ablation-resistant tungsten nosetip include: a) no blunting-induced drag increase, b) maximum ballistic coefficient, c) straightforward maintenance of a positive static margin and no ablation-induced trim for aerodynamically stabilized projectiles, d) forward-located center of gravity and no signal attenuation due to ablation products for guided projectiles, and e) ability to survive severe launch loads and thermal shock. This oxidation-resistant heat-sink thermal protection technology is potentially applicable to other military and commercial systems such as gun-launched access to space capsules, hypervelocity vehicle leading edges and control surfaces, rocket and jet engine components, and certain high-temperature cathodes and filaments.