Tooling design and microwave curing technologies for the manufacturing of fiber-reinforced polymer composites in aerospace applications

The increasing demand for high-performance and quality polymer composite materials has led to international research effort on pursuing advanced tooling design and new processing technologies to satisfy the highly specialized requirements of composite components used in the aerospace industry. This paper reports the problems in the fabrication of advanced composite materials identified through literature survey, and an investigation carried out by the authors about the composite manufacturing status in China’s aerospace industry. Current tooling design technologies use tooling materials which cannot match the thermal expansion coefficient of composite parts, and hardly consider the calibration of tooling surface. Current autoclave curing technologies cannot ensure high accuracy of large composite materials because of the wide range of temperature gradients and long curing cycles. It has been identified that microwave curing has the potential to solve those problems. The proposed technologies for the manufacturing of fiber-reinforced polymer composite materials include the design of tooling using anisotropy composite materials with characteristics for compensating part deformation during forming process, and vacuum-pressure microwave curing technology. Those technologies are mainly for ensuring the high accuracy of anisotropic composite parts in aerospace applications with large size (both in length and thickness) and complex shapes. Experiments have been carried out in this on-going research project and the results have been verified with engineering applications in one of the project collaborating companies

Fresh air funds and functional families: The enduring politics of race, family and place in juvenile justice reform

This article examines the enduring ways that racial politics are masked by discourses of place and family in the history of juvenile justice in the USA. The tropes of place and family have been invoked since the inception of the USA’s juvenile justice system and have influenced the processes of policing, removal, and return, even as the latest incarnation of reforms focus on building juvenile justice facilities and alternatives to incarceration within urban areas. By pointing to recent manifestations of this rhetoric in New York, the article identifies the thread that links these claims together: the desire by social control agents for submission by the primarily impoverished and young people of color who defy legal authority

Erosion Testing of Protective Coatings and Surface or Bulk Modification Treatments for Turbine Compressor Gas Path Components

NRC publication: Ye

UMS Al-Mo Coatings as an Alternative to Electro-plated Cadmium

NRC publication: Ye

Results of Cyclic Oxidation and Hot Corrosion Burner Rig Tests on Abradable Seal Coatings

NRC publication: Ye

Development of UMS Al-Mo Coatings for Cadmium Replacement in Aerospace Applications (ABSTRACT)

Peer reviewed: YesNRC publication: Ye

Evaluation and qualification of diffusion braze repair techniques for superalloy gas turbine components

This paper reports on the development of Diffusion Braze Repair (DBR) techniques for service damaged turbine engine nozzle guide vanes (NGVs), made from cobalt and nickel-base superalloys. A description of the work undertaken by Vac-Aero in collaboration with the Institute for Aerospace Research of the National Research Council on qualification of the repair techniques for aero engine applications is also provided. This qualification work included bench testing of material test coupons as well as accelerated endurance testing of repaired aero engine parts under simulated service conditions in a burner rig. The results of stress rupture and burner rig tests indicate that Diffusion Braze Repair is an attractive and viable alternative to component replacement.NRC publication: Ye

IAR Infrastructure for Certification of Life Extension Technologies Applicable to Turbine Components

NRC publication: Ye

Thickening behaviour of y'-precipitates in nickel base superalloys during rafting

NRC publication: Ye