关于用预应力UHPC制成的深度绘制模具的实验研究
Katja Holzer1, Yuqi Zhang1, Lukas Martinitz1
1Chair of Metal Forming and Casting, Technical University of Munich, Walther-Meissner-Strasse 4, 85748 Garching, Germany.
Materials (Basel, Switzerland)
|January 25, 2025
概括
超高性能混凝土 (UHPC) 显示出对具有成本效益的深度绘图工具的承诺. 在试验中,用钢筋装备预应力膨胀型超高压电压器提高了工具性能,改变了故障模式并增加了负载能力.
科学领域:
- 材料科学 材料科学 材料科学
- 制造业 工程 制造工程
背景情况:
- 深度绘制是一种高体积的金属板成型工艺.
- 对于原型和小型系列来说,传统的钢制工具是昂贵的.
- 超高性能混凝土 (UHPC) 提供了一个具有成本效益的替代方案,但其强度限制阻碍了复杂的应用.
研究的目的:
- 为了研究使用膨胀剂和机械制的超高性能混凝土 (UHPC) 预应力.
- 评估该方法在提高HHPC适用于深度绘图应用中的有效性.
主要方法:
- UHPC被修改为以粉为基础的膨胀剂,以诱导自由体积增加.
- 推出测试是在用钢筋加强的标本上进行的,以抑制膨胀和测量强度增加.
- 在限制条件下,使用由膨胀型UHPC制成的模具进行了深度绘图实验.
主要成果:
- 在3个月和12个月后的推出测试中,没有测量出显著的训练前效应.
- 由受约束的膨胀型UHPC制成的深绘模具可以承受110 kN的最大负载.
- 故障模式从完全断裂 (仅UHPC) 转变为15次冲击后绘图半径的表面退化.
结论:
- 约束式膨胀型UHPC显示出深度绘制应用的潜力,尽管可测量的预应变有限.
- 与标准的UHPC相比,修改后的UHPC模具具有更好的耐用性和承载能力.
- 这种方法提供了一个可行的,成本效益高的解决方案,用于板材成型的工具加工.
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