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A<sc>bstract</sc> We apply the joint threshold and transverse momentum dependent (TMD) factorization theorem to introduce new threshold-TMD distribution functions, including threshold-TMD parton distribution functions (PDFs) and fragmentation functions (FFs). We apply Soft-Collinear Effective Theory and renormalization group methods to carry out QCD evolution for both threshold-TMD PDFs and FFs. We show the universality of threshold-TMD functions among three standard processes, i.e. the Drell-Yan production inppcollisions, semi-inclusive deep-inelastic scattering and back-to-back two hadron production ine+e−collisions. In the end, we present the numerical predictions for different threshold-TMD functions and also transverse momentum distributions atpp,ep, ande+e−collisions.
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Joining of metal and non-polar polypropylene composite through a simple functional group seeding layer
Polypropylene (PP) and its composites are one of the hardest to directly join with metals due to their inherent chemical incompatibility. This paper presents a simple, efficient, and cost-effective method for joining PP composite to aluminum alloy in spot welding configuration by seeding the functional groups via an insert layer of PA6 thin film without requiring surface or material pre-treatment. The resulting joint loading capacity is shown to be sufficiently high to consistently develop failures in PP substrates in lap shear tensile tests away from the bonded area. Joint interface microstructure features are examined in detail. Bonding mechanisms are then described based on the detailed observations obtained in this study.
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- Award ID(s):
- 2126163
- PAR ID:
- 10475454
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal of Manufacturing Processes
- Volume:
- 85
- Issue:
- C
- ISSN:
- 1526-6125
- Page Range / eLocation ID:
- 90 to 100
- Subject(s) / Keyword(s):
- Polymer composites Metal to polymer joining Friction spot welding Aluminum alloy Multi-material Surface pre-treatment Bonding interface Hybrid structures
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1016/j.jmapro.2022.11.022
