粘合接触的模拟是否足以模拟牙剪接强度测试中的非线性失效行为?
Ahmed M Ismail1, Ahmed ElBanna2, Tamer M Nassef3
1Oral Technology, University Hospital Bonn, Bonn, Germany; Biomaterials Department, Faculty of Dentistry, Ain Shams University, Cairo, Egypt.
International dental journal
|April 6, 2025
概括
研发了剪接强度测试的数值模型,发现独特的剪接和正常应力极限不能普遍预测不同样本大小和加载方法的故障. 每个设置都需要特定的限制.
科学领域:
- 生物材料科学 生物材料科学
- 牙科材料 牙科材料
- 有限元分析 有限元分析
背景情况:
- 精确模拟剪接强度 (SBS) 测试对于评估牙科修复材料至关重要.
- 现有的模型往往简化了样本大小,加载技术和故障机制之间的复杂相互作用.
- 了解这些因素是可靠材料表征和性能预测的关键.
研究的目的:
- 开发和验证一个有限元模型来模拟SBS测试.
- 调查样本大小 (宏观与微观) 和加载技术 (丝与线圈) 对结合强度预测的影响.
- 为了确定一套通用的失败标准是否可以准确地代表不同测试配置的实验结果.
主要方法:
- 创建了一个3D有限元模型,结合复合材料,牙,牙质,烯酸树脂和聚烯管.
- 四个不同的模型模拟了在 chisel 或线圈负载下的宏观 (1.8 毫米) 和微型 (0.8 毫米) 标本.
- 使用基于接触的粘合剂故障标准模拟渐进性故障,仅分析剪切应力 (系列1) 和结合剪切/正常应力 (系列2),并将应力极限与实验数据相匹配.
主要成果:
- 第1系列的模拟成功地使用特定组的剪切应力极限复制了实验失效力:71 MPa (宏/线),48 MPa (微/线),106 MPa (宏/),和131 MPa (微/).
- 系列2模拟,包括剪切和正常应力,未能确定适用于所有测试组的单一,独特的应力极限对.
- 这表明故障机制对SBS测试设置的特定几何和负载条件敏感.
结论:
- 有限元模型可以模拟SBS测试,但对于不同的样品大小和加载方法需要不同的剪切应力极限.
- 一个单一的,结合的剪切和正常应力失效标准不足以预测所有测试配置的结合强度.
- 该研究强调了SBS测试的复杂性和基于实验设置几何学的定制模拟参数的需求.
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