Abstract This study investigates the effect of autoclave curing variables on the glass transition temperature of and the degree of cure and strength of epoxy film adhesive single lap joints (SLJs) under static tensile shear loading. Studied autoclave variables include the cure temperature, cure pressure, temperature, and pressure ramp rates on the glass transition temperature as well as the cure time duration. Test joints are made of Aluminum substrates that are autoclave-bonded using epoxy film adhesive (AF163-2k). For each variable combination of the autoclave process, the corresponding glass transition temperature of cured Epoxy film adhesive is obtained using Dynamic Mechanical Analysis (DMA-Q800). Test data are generated for both baseline joints [uncycled] as well as for joints that have been heat-cycled in an environmental chamber after initial autoclave bonding. Results show a strong correlation between the autoclave process variable combinations and the corresponding glass transition temperature bond strength, and the failure mode of test joints. 
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                            A Review on the Out-of-Autoclave Process for Composite Manufacturing
                        
                    
    
            Composite materials have gained increased usage due to their unique characteristic of a high-stiffness-to-weight ratio. High-performing composite materials are produced in the autoclave by applying elevated pressure and temperature. However, the process is characterized by numerous disadvantages, such as long cycle time, massive investment, costly tooling, and excessive energy consumption. As a result, composite manufacturers seek a cheap alternative to reduce cost and increase productivity. The out-of-autoclave (OoA) process manufactures composites by applying vacuum, pressure, and heat outside of the autoclave. This review discusses the common out-of-autoclave processes for various applications. The theoretical and practical merits and demerits are presented, and areas for future research are discussed. 
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                            - Award ID(s):
- 1950500
- PAR ID:
- 10502508
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Journal of Composites Science
- Volume:
- 6
- Issue:
- 6
- ISSN:
- 2504-477X
- Page Range / eLocation ID:
- 172
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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