【正文】 C. The superior formability of LZ91 sheet at room temperature was also demonstrated in the present study by successful manufacturing of the notebook top cover case. The proposed fouroperation process lends itself to an efficient approach to form the hinge in the notebook with fewer operational procedures than that required in the current practice. 14 It also confirms that the notebook cover cases can be produced with LZ91 magnesium alloy LZ91 sheet by the stamping process. It provides an alternative to the electronics industry in the application of magnesium alloys. Acknowledgments The authors would like to thank the National Science Council of the Republic of China for financially supporting this research under the Project No. NSC952622E002019CC3, which made this research possible. They would also like to thank ESI, France for the help in running the PAM_STAMP program. References 1. o Chen and Huang, 2020 o . Chen, . Huang o Formability of stamping magnesiumalloy AZ31 sheets o J. Mater. Process. Technol., 142 (2020), pp. 643–647 o 2. o Chen et al., 2020 o . Chen, . Huang, . Chang o Deep drawing of square cups with magnesium alloy AZ31 sheets o Int. J. Mach. Tools Manuf., 43 (2020), pp. 1553–1559 o 3. o Drozd et al., 2020 o Z. Drozd, Z. Trojanov225。 Reprints Abstract In the present study, the stamping process for manufacturing a notebook top cover case with LZ91 magnesium–lithium alloy sheet at room temperature was examined using both the experimental approach and the finite element analysis. A fouroperation stamping process was developed to eliminate both the fracture and wrinkle defects occurred in the stamping process of the top cover case. In order to validate the finite element analysis, an actual fouroperation stamping process was 7 conducted with the use of mm thick LZ91 sheet as the blank. A good agreement in the thickness distribution at various locations between the experimental data and the finite element results confirmed the accuracy and efficiency of the finite element analysis. The superior formability of LZ91 sheet at room temperature was also demonstrated in the present study by successful manufacturing of the notebook top cover case. The proposed fouroperation process lends itself to an efficient approach to form the hinge in the notebook with less number of operational procedures than that required in the current practice. It also confirms that the notebook cover cases can be produced with LZ91 magnesium alloy sheet by the stamping process. It provides an alternative to the electronics industry in the application of magnesium alloys. Keywords ? Notebook case。首先研究了 AZ31和LZ 的成形性。然后制造一個完善的產品無斷裂和皺紋，如圖 6（ a）所示。在第三步的折疊過程中產生過多的物質，然后根據(jù)零件設計，修剪掉。成功地避免了這樣的過程，同時形成兩個幾何特征的難度，但增加了一張白紙的物質流。圖 4（ c）所示的厚度分布的有限元模擬得到。這意味著斷裂問題非常嚴重，是只通過擴大在法蘭圓角半徑是不能解決的。被視為剛體的工具，并采用四節(jié)點殼單元建設空白網(wǎng)。 C 是彼此接近。造成這種幾何復雜 圓角半徑的一個戲劇性的變化時，鉸鏈法蘭太接近筆記本的邊緣，這很容易造成周圍的鉸鏈法蘭斷裂缺損，并要求多操作，克服這一問題。由于它的六角形密堆積（ HCP 的形成）晶體結構（ [陳等， 2020]和 [陳和黃，2020]），即使它需要高溫，常 用沖壓工藝中鎂合金（鋁 3％，鋅 1％）已在目前的形成過程中應用。適合的四步操作過程本身操作程序數(shù)量少，比在目前的實踐要求，形成在筆記本鉸鏈的有效途徑。為了驗證有限元分析，進行實際操作沖壓工藝與使用 毫米厚的 LZ91 的空白。多工序沖壓 。 在本研究中，一個筆記本頂蓋使用 LZ 表的情況下的沖壓工藝進行了檢查。圖 2（ a）顯示 LZ 表在室溫和那些對 AZ31 張在室溫和 200176。 圖 2 鎂合金的力學性能 （ a） 鎂合金的應力應變關系 。 首次構建了有限元模型研究的一個鉸鏈的形成過程。對避免斷裂，提出了幾種方法，斷裂問題的一個可行的解決方案是四 個操作沖壓工藝。因此，即使兩個操作沖壓工藝 解決在角落和底部的鉸鏈法蘭斷裂問題，更好的形成過程仍有望解決鉸鏈法蘭起皺。當額外的工作表不修剪，在拐角處的厚度為 毫米，如圖 5（ d）所示。 5。 表 1。 同時證明了筆記本蓋，可以用 LZ91， LZ91 鎂合金板的沖壓工藝生產。C are close to each other. LZ101 sheet at room temperature exhibits even better ductility than LZ91 and AZ31 do at 200 176。 2020 Elsevier . All rights reserved. Related articles Tangential bending and stretching of thin ma... Materials amp。 ? Formability 1. Introduction Due to its lightweight and good performance in EMI resistance, magnesium alloy has been widely used for structural ponents in the electr