澳洲5在线计划
C(f) or SiC(f) - C, SiC, HfC, ZrC, NbC, TaC, TiC, B4C, HfB2, Mo,Zr,Hf Ir, Nb, Re
Fabrication of CMC components via a low-cost, rapid CVI process based on a gas-pulsed, reverse thermal gradient CVI (GP-RTG CVI)
- Hypersonic propulsion, “zero erosion” nozzle liner
- Divert attitude propulsion (DACS) thrusters
- Ion optics C(ϝ)/C grids
- Long-life, fiber interface coatings
- Lightweight injectors for DACS
- Graded Cf- SiC/HfC CMCs for Liquid Rocket Nozzles
Low-Cost Approach to CMCs
Develop processing approaches to fabricate CMCs at significantly lower costs than by conventional means
- Large ∆T – directional matrix growth, Functionally Graded Matrices
- Higher T&P – higher matrix growth rate
- Colder surface – maintains open surface porosity
- Cycling P – maintains high matrix growth rates
- Reactant consumption reduced considerably
- Allows variable matrix architectures
- Reduced processing/component costs
- Six-fold reduction in time, ten-fold reduction in cost
澳洲5历史走势图
| X |
p (g/cc) Monolith |
p (g/cc) Cf/X |
p (g/cc) Cf/C-X |
p (g/cc) Cf/SiC-X |
|---|---|---|---|---|
| C | 1.8 – 2.1 | ~1.95 | ~1.95 | - |
| SiC | 3.22 | 2.25 | 1.81 | - |
| Re | 20.53 | 10.04 | 3.37 | 3.85 |
| HfC | 13.31 | 6.79 | 2.72 | 3.17 |
Assume: 40 vol% fibers and 15% porosity
澳洲5开奖走势图
Objective:
- To establish multiple-use thrust cells for 3rd generation RLV applications
- Establish cooled composite designs for use with LH₂/LOₓ fuels
- Demonstrate firing of liquid H₂ cooled CMC design
Results:
- C(f)/C-HfC₉₀/SiC₁₀ was selected and tested
- Three nozzles were fabricated and tested – surviving for more than 250 seconds at 4700˚F
- At chamber pressures of 500psi, CMC showed gas permeability
- No throat erosion was observed following 250 seconds at 4700˚F
澳洲5开奖走势图
Objective:
- Demonstrate low-cost, rapid CVI process for the fabrication of C(r)/SiC DACS thrusters
- Demonstrate significant cost reduction over existing Noveltex DACS thrusters (THAAD)
- Establish TA&T as a low-cost, second-source supplier of CMC DACS thrusters
Results:
- Established a rapid CVI process based on GP-RTG CVI
- Densified C(r)/SiC thrusters to ~85% in less than 40 hours
- Developed fully automated process control system for majority of CMC processing
- Demonstrated directional matrix growth and optimized process for DACS thrusters
PVD Magnetron Sputtered Coatings
Magnetron sputtered coatings – multilayered:
- Residual stresses significantly influence the coating bulk properties
- Developing process control to determine residual stress, texture, surface roughness, etc. of coating during growth
Properties:
- Thermal EBCS for SiC CMCs up to 2850oF
- Wear resistance – B₄C/SiC, B₄C/W, etc.
- Solid Lubrication – MoS₂/Au-Pd
- Quasicrystalline/Nanocrystalline coatings
- CrN/Cr2N Corrosion Resistant
