Curtis Hickmott, A. Forghani, Victoria Hutten, Evan Lorbiecki, F. Palmieri, B. Grimsley, B. Coxon, G. Fernlund, A. Poursartip
{"title":"一种模拟复合材料结构制造过程中因夹持空气和挥发物逸出而导致孔隙度的数值和实验方法","authors":"Curtis Hickmott, A. Forghani, Victoria Hutten, Evan Lorbiecki, F. Palmieri, B. Grimsley, B. Coxon, G. Fernlund, A. Poursartip","doi":"10.33599/NASAMPE/S.19.1627","DOIUrl":null,"url":null,"abstract":"High performance composite structures have strict requirements regarding acceptable levels of porosity. The impact can be significant on mechanical performance and mitigating the growth of voids can be a challenge given the complexity of the problem. The evolution of porosity can be summarized as a balance between sources and sinks which determine void growth or shrinkage. The primary sources of void growth include bag leaks, entrapped air in the system, off-gassing of volatiles, and cure shrinkage. Mechanisms which mitigate porosity include removal of air from the system and maintaining sufficient resin pressure during the process to keep volatiles in solution. In this paper, an approach for modeling the evolution of voids due to entrapped air and volatiles is presented. It has been shown in previous experimental studies that decreases in local resin pressure are linked to a higher likelihood of porosity formation. Results of the study are compared to experiments in which the local resin pressure was measured and micrographs of the panels were taken to characterize the porosity.","PeriodicalId":162077,"journal":{"name":"SAMPE 2019 - Charlotte, NC","volume":"8 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2019-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"A Numerical and Experimental Approach for Modeling Porosity Due to Entrapped Air and Volatiles Off-gassing During Manufacturing of Composite Structures\",\"authors\":\"Curtis Hickmott, A. Forghani, Victoria Hutten, Evan Lorbiecki, F. Palmieri, B. Grimsley, B. Coxon, G. Fernlund, A. Poursartip\",\"doi\":\"10.33599/NASAMPE/S.19.1627\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"High performance composite structures have strict requirements regarding acceptable levels of porosity. The impact can be significant on mechanical performance and mitigating the growth of voids can be a challenge given the complexity of the problem. The evolution of porosity can be summarized as a balance between sources and sinks which determine void growth or shrinkage. The primary sources of void growth include bag leaks, entrapped air in the system, off-gassing of volatiles, and cure shrinkage. Mechanisms which mitigate porosity include removal of air from the system and maintaining sufficient resin pressure during the process to keep volatiles in solution. In this paper, an approach for modeling the evolution of voids due to entrapped air and volatiles is presented. It has been shown in previous experimental studies that decreases in local resin pressure are linked to a higher likelihood of porosity formation. Results of the study are compared to experiments in which the local resin pressure was measured and micrographs of the panels were taken to characterize the porosity.\",\"PeriodicalId\":162077,\"journal\":{\"name\":\"SAMPE 2019 - Charlotte, NC\",\"volume\":\"8 1\",\"pages\":\"0\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2019-04-11\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"SAMPE 2019 - Charlotte, NC\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.33599/NASAMPE/S.19.1627\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"SAMPE 2019 - Charlotte, NC","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.33599/NASAMPE/S.19.1627","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
A Numerical and Experimental Approach for Modeling Porosity Due to Entrapped Air and Volatiles Off-gassing During Manufacturing of Composite Structures
High performance composite structures have strict requirements regarding acceptable levels of porosity. The impact can be significant on mechanical performance and mitigating the growth of voids can be a challenge given the complexity of the problem. The evolution of porosity can be summarized as a balance between sources and sinks which determine void growth or shrinkage. The primary sources of void growth include bag leaks, entrapped air in the system, off-gassing of volatiles, and cure shrinkage. Mechanisms which mitigate porosity include removal of air from the system and maintaining sufficient resin pressure during the process to keep volatiles in solution. In this paper, an approach for modeling the evolution of voids due to entrapped air and volatiles is presented. It has been shown in previous experimental studies that decreases in local resin pressure are linked to a higher likelihood of porosity formation. Results of the study are compared to experiments in which the local resin pressure was measured and micrographs of the panels were taken to characterize the porosity.