Development of wood forming method with high hydrostatic pressure that achieves large deformation and high strength

开发实现大变形、高强度的高静水压木材成型方法

• 批准号: 22K04773
• 负责人: 梶川 翔平
• 金额: $ 2.66万
• 依托单位: The University of Electro-Communications
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2022
• 资助国家: 日本
• 起止时间: 2022-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-22K04773/
• 关键词: 木材・木質材料; 塑性加工; 静水圧効果; 大変形; 金型

2022年度は，密度が異なる2種類の材料（スギ，ウリン）に対して簡易金型を用いた鍛造加工実験を行い，鍛造加工時における静水圧状態が小型容器の成形性に及ぼす影響を調査した．また，高静水圧プレス金型の設計および製作を行った．主な実績は以下の通りである．(1) 鍛造加工時において，内部に空隙が多いスギ材と比べ，高密度なウリン材の場合に流動変形が生じやすい傾向を示した．スギの場合，圧密変形量は大きいものの，圧密完了後の流動変形が生じにくい．(2) プレス方向に対する木材の年輪方向によって，変形挙動は大きく変化した．繊維方向に圧縮する場合，繊維間の剥離が生じやすく，パンチが接触する部分のみが圧密され，高密度化しやすい．一方，半径方向に圧縮する場合，材料全体が圧密・高密度化しやすい傾向を示した．特に，加工初期から高密度なウリン材の場合，半径方向圧縮の場合において，高密度化からの流動変形が生じやすいことがわかった．(3) 形状が異なる種々のパンチを用いることによって，鍛造加工時における材料の静水圧状態を変化させた結果，静水圧が高いほど型の端部まで充填しやすく，成形品密度も向上した．一方で，型端部にて材料を十分に圧密するためには，金型・木材間の摩擦の低減も必要であることが示唆された．(4) 高静水圧プレス金型の設計を行った．本金型を用いることによって，下部から背圧を加えた状態で，木材をプレスし，変形させることができる．簡易金型を用いた鍛造加工実験の結果に基づき，必要となる背圧や，金型の表面処理の検討なども完了した．

In 2022, two kinds of materials with different densities were investigated for the influence of hydrostatic pressure on the formability of small containers during forging. The design and production of high hydrostatic pressure metal models. The Lord's performance is the following. (1)During forging process, the internal void is more than the material ratio, and the flow shape tends to occur in the case of high density material. In case of pressure change, the pressure change quantity is large, and the flow change quantity is generated after the pressure is completed. (2)The direction of wood growth is different from the direction of wood growth. In the case of dimensional compression, the separation between the dimensions is generated, and the contact part is compressed and densified. In the case of radial compression, the material as a whole tends to be dense and dense. In particular, in the early stage of processing, when the density of the material is high, the radial direction is compressed, and the flow shape of the high density is generated. (3)The hydrostatic pressure state of the material changes during the forging process. As a result, the hydrostatic pressure changes from high to low, and the end of the shape changes from high to low. The density of the molded product increases. The material on the end of the mold is very tight and the friction between the mold and the wood is very low. (4)High hydrostatic pressure, high pressure, The main type is used in the middle, the lower part is used in the back, the upper part is used in the back, the lower part is used in the back, and the lower part is used in the back. Simple gold mold with middle forging processing results in basic, necessary, back pressure, gold mold surface treatment and research finished.