SBIR Phase II: Chemical Vapor Deposition-SiC Coated Ceramic Valve Components of High Damage and Wear Resistance

SBIR第二期：化学气相沉积-SiC涂层高损伤和耐磨陶瓷阀元件

• 批准号: 9800946
• 负责人: Jan-Fong Jue
• 金额: $ 40万
• 依托单位: MATERIALS & SYSTEMS RESEARCH INC
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-01 至 2000-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9800946&HistoricalAwards=false
• 关键词: SBIR; Phase; II; Chemical; Vapor

*** 9800946 Jue This Small Business Innovation Research Phase II project will demonstrate significant improvements in resistance to corrosion, erosion and fracture and service lifetimes for valves with the graded silicon carbide (SiC) components to be developed relative to the valves with sintered alpha-SiC components. SiC is a low-cost ceramic that possesses high hardness, good sliding wear resistance, and excellent corrosion and oxidation resistance. Because of these attributes it is used as mechanical face seals for water pumps in automobiles and as balls and seats in shut-off valves. SiC, however, has a low fracture toughness that renders it susceptible to fracture under impact and thermal-shock conditions and to surface damage and erosion in particle impact. During Phase I, the feasibility of toughening SiC was demonstrated. The approach used consisted of designing and fabricating a functionally-graded material where the outer layer was 'pure' beta-SiC deposited by chemical-vapor deposition (CVD) on a substrate made of liquid-phase sintered SiC-TiC particulate composite. The designed composition and thermal-expansion mismatch led to a residual surface compression in the CVD-SiC coating on cooling from the deposition temperature. Coating compressions as high as 1.1 GPa were developed by this approach depending on the substrate composition, coating thickness, and the geometry of the component. Surface compression in the graded-SiC increased rolling-contact-fatigue life by greater than a factor of 100. The Phase II research will apply this technology to balls and seats in a 1.5 in. ball valve manufactured and marketed by Valtek International, the Phase III partner. Development of a ceramic manufacturing process for making SiC-TiC balls and seats, optimization of a rapid chemical-vapor deposition/composite vapor coating (CVD/CVC) coating process, low-cost surface finishing and prototype and field testing of the valve components are the major tasks in the proposed research. Th e Phase II research project is aimed at introducing surface-compression-toughened SiC in ceramic ball valves. These valves accounted for $ 8 million in sales in North America in 1996. The technology can also be implemented in the ceramic bearing and the automobile industries , e.g., cam followers. ***

* 9800946爵 该小型企业创新研究第二阶段项目将证明，相对于烧结α-SiC组件的阀门，将开发的分级碳化硅（SiC）组件的阀门在耐腐蚀性、耐侵蚀性和耐断裂性以及使用寿命方面有显着改善。 SiC是一种低成本的陶瓷，具有高硬度、良好的滑动耐磨性以及优异的耐腐蚀性和抗氧化性。 由于这些属性，它被用作汽车水泵的机械面密封和截止阀的球和座。 然而，SiC具有低的断裂韧性，这使得其在冲击和热冲击条件下易于断裂，并且在颗粒冲击中易于表面损伤和侵蚀。 在第一阶段，证明了增韧SiC的可行性。 所使用的方法包括设计和制造一种功能梯度材料，其中外层是通过化学气相沉积（CVD）在液相烧结SiC-TiC颗粒复合材料制成的基底上沉积的“纯”β-SiC。设计的组合物和热膨胀失配导致CVD-SiC涂层在从沉积温度冷却时的残余表面压缩。 涂层压缩高达1.1 GPa的开发，通过这种方法取决于基板的组合物，涂层厚度，和组件的几何形状。 梯度SiC中的表面压缩使滚动接触疲劳寿命增加了100倍以上。 第二阶段的研究将把这项技术应用到1.5英寸的球和座位上。球阀由Valtek International（第三阶段合作伙伴）制造和销售。 开发用于制造SiC-TiC球和阀座的陶瓷制造工艺，优化快速化学气相沉积/复合气相涂层（CVD/CVC）涂层工艺，低成本表面精加工以及阀组件的原型和现场测试是拟议研究的主要任务。 第二阶段研究项目的目的是在陶瓷球阀中引入表面压缩增韧SiC。 这些阀门1996年在北美的销售额为800万美元.该技术还可以在陶瓷轴承和汽车工业中实施，例如，凸轮从动件。 ***