Thesis
The effects of carbon fiber orientation and type on tool wear and the machined surface quality in edge trimming of carbon fiber reinforced polymer (CFRP) composites
Washington State University
Master of Science (MS), Washington State University
05/2020
DOI:
https://doi.org/10.7273/000004033
Handle:
https://hdl.handle.net/2376/124890
Abstract
Carbon fiber reinforced polymers (CFRPs) are widely used in various high-tech industries, including aerospace, automotive, wind, or marine. Generally, when CFRP is cured to near final shape, finishing operations such as edge trimming, milling or drilling is required to remove excess material for finishing and/or the final assembly. The service life of CFRP components depends to a great extent on the quality of machining. However, due to their inhomogeneous nature, many problems such as rapid tool wear, poor surface roughness, fiber pullout, uncut fibers and matrix smearing may occur during the machining processes. This study aims to investigate the effect of carbon fiber's type and orientation on tool wear and surface quality when the CFRP laminates are edge-trimmed. Three different carbon fiber materials are used in the study, namely the PAN-based standard modulus (SM) fiber of T300, the intermediate modulus (IM) fiber of IM7, and the pitch-based high modulus (HM) fiber of K13312. The edge trimming process experiments used four different tool path lengths (1m, 4m, 8m, and 16m) at different fiber orientations (0-, 45-, 90-, and 135-degree) at the consistent tool spindle speed of 6000 RPM. The tool wear width as well as machined tool surface after different tool path length are investigated using a Scanning Electron Microscope (SEM). In terms of quality parameters, research focuses on surface roughness and material integrity. Wear mechanisms are also discussed from SEM images observation. The experimental results show that the IM carbon fibers create more tool wear than the SM carbon fibers or the HM carbon fibers. Both hard abrasion and soft abrasion can be found at the worn tool surface for the IM coupons. Hard abrasion is a dominant mechanism for the SM coupons, while soft abrasion is a dominant mechanism when machining HM coupons. When it comes to the effect of fiber orientation on tool wear, 45-degree fibers create the most tool wear followed by 90-degree fibers. The surface roughness of CFRP increases with the increasing tool path length, which is due to tool wear. Uncut carbon fibers are the dominant rough composition on 45-degree machined CFRP surfaces. Fiber pullouts are mostly displayed on 135-degree surfaces. Uncut glass fiber wefts can become a main reason of the poor surface roughness of machined CFRP surface when tools are worn.
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Details
- Title
- The effects of carbon fiber orientation and type on tool wear and the machined surface quality in edge trimming of carbon fiber reinforced polymer (CFRP) composites
- Creators
- Yinyin Han
- Contributors
- Dae-Wook Kim (Advisor) - Washington State University, School of Engineering and Computer Science (VANC)
- Awarding Institution
- Washington State University
- Academic Unit
- School of Engineering and Computer Science (VANC)
- Theses and Dissertations
- Master of Science (MS), Washington State University
- Publisher
- Washington State University
- Identifiers
- 99900890794701842
- Language
- English
- Resource Type
- Thesis