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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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Latent Activation Limited Failure Models, Stochastic Ordering and Identifiability
ABSTRACT Limited failure or cure rate models provide generalization of lifetime models which allow the possibility of subjects or units to be cured or be failure‐free. While modeling and analysis of such models are extensively studied, we study the important question of identifiability of these models. We discuss the latent and hierarchical activation cure models and establish a series of results on stochastic ordering within these models. We also establish a series of results on identifiability of these models under various conditions. Further, we demonstrate multiple cases where there models are not identifiable and illustrate the potential difficulty with these models in a simulation study.
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- Award ID(s):
- 2413549
- PAR ID:
- 10569530
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Applied Stochastic Models in Business and Industry
- Volume:
- 41
- Issue:
- 1
- ISSN:
- 1524-1904
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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