B型チタン合金の短時間加工時効法の確立

B型钛合金短时加工时效方法的建立

• 批准号: 09750112
• 负责人: 森田 辰郎
• 金额: $ 1.28万
• 依托单位: Kyoto Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Encouragement of Young Scientists (A)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-09750112/
• 关键词: β型チタン合金; 塑性加工; 高周波誘導加熱; 短時間時効; 硬さ; 微視組織

本年度は,表記研究の第1段階として試験片作製および塑性加工方法を確立し,さらに塑性変形量と硬さおよび微視組織の関係について検討後,塑性加工・熱処理条件を決定した.具体的には下記の通りである.1,試験片:溶体化処理(1123K,0.5h)を施したβ型チタン合金Ti-20V-4Al-1Sn板材を放電加工により角棒状に切出した後,平面切削により幅10×厚さ12×長さ180mmの形状に機械加工した.この試験片の長さ方向の中央部に,焼入れした工具用鋼SKD11(直径23mm)を上下各1本用いて塑性変形を加えた.その際,試験片軸を直線に維持しつつ圧縮比((元の厚さ-変形後の厚さ)/元の厚さ)70%以上まで塑性加工可能な自作持具を用いた.2,予備試験:上記の持具を用いて圧縮比10〜70%の条件で塑性加工したチタン合金について,マイクロビッカース硬さの測定および微視組織の観察を行った.溶体化時の硬さはHV270であったが,塑性変形量の増大に比例して硬さは上昇し,圧縮率70%ではHV330となった.このような硬さの上昇は,時効時に溶質原子あるいは微細α相の優先的な析出位置としての役割を果たす転位が増殖したことを示しており,時効の加速現象の発現が期待される.また,圧縮率の増大にともない結晶粒は等軸状から極端な偏平状へ変化しており,これは本試験片の荷重方向を考慮すれば結晶粒の微細化と同等の効果を強度に及ぼすと考えられる.3,塑性加工・熱処理条件:時効の加速現象は圧縮率が大であるほど顕著に発現し得るので,まず塑性加工条件として圧縮率70%を選択した.高周波時効条件は,短時間に時効効果を発現させるために急速昇温後,時効温度としては比較的高温である873,973および1073Kの3条件で60s間保持とした.なお,前述の試験片形状は誘導加熱に若干不向きなため,新たに高周波加熱コイルを作製し,現在熱処理中である.

This year, the first stage of the table study was to establish the method of making and plastic processing of test pieces. After the relationship between plastic deformation, hardness and Weishi app structure was discussed, the conditions of plastic processing and heat treatment were determined. Specific details are as follows: Sample: Solution treatment (1123K, 0.5h) β-type alloy Ti-20V-4Al-1Sn plate is machined in the shape of 10× 12× 180mm thick after cutting out the angle rod. In the center of the length direction of the test piece, the tool steel SKD11(diameter 23mm) was burned, and the plastic deformation of the upper and lower parts was added. At this time, the pressure ratio ((Yuanのthickness-thickness after deformation)/Yuanのthickness) of more than 70% is maintained when the test piece shaft is straight. Therefore, plastic processing may be possible with a self-made holder. 2, prepare for the test: The above holder can be used with a pressure ratio of 10 ~ 70% to allow plastic processing of the alloy, and the measurement of the hardness of the Weishi app can be performed on the micro-vision tissue. During dissolution, the hardness increases from HV270 to HV 330, the plastic deformation increases from HV 270 to HV 330, and the hardness increases from HV 270 to HV330. The rise of the hard phase is expected to occur at the preferential precipitation position of the solute atom and at the preferential precipitation position of the fine alpha phase. For example, the increase in the compression ratio of the crystalline particles is equiaxed, extremely flat, and the load direction of the test piece is considered. For example, the refinement of the crystalline particles and the equivalent effect are considered. 3. The plastic processing and heat treatment conditions are selected such that the compression ratio is 70% due to the increase in the compression ratio. High frequency wave time condition, short time effect appears, rapid temperature rise, time temperature is relatively high temperature, 873,973 K, 3 conditions are maintained for 60s. The shape of the test piece mentioned above is not only induced by heating, but also by high frequency heating.