为了探索提高AZ31镁合金板材室温冲压性能的途径,通过断口形貌分析,对板材室温拉深变形过程中的破裂机理进行了研究.结果表明,室温下,对于普通轧制板材,在拉深比达到1.2后即在冲头肩部发生破裂;对于等径角轧制板材.其拉深比可达1.6以上;当拉深比达到1.8时,在杯形件凸缘发生破裂,断面光滑平整.为解理断裂.这主要与板材在拉深变形中的应力应变状态和其非基面织构有关.单向拉伸与断口分析表明其冲压性能和破裂行为的差异,主要是因为这两种板材织构不同所致.
The fracture mechanism of AZ31 magnesium alloy sheet in deep drawing deforming was investigated by analyzing fracture morphology in order to find a method to improve drawability at room temperature. The results indicate that the crack for the sheet produced by normal rolling (NR) appeares at the shoulder of the cup drawn with the drawing ratio of 1.2 and the fracture for the sheet produced by equal channel angular rolling (ECAR) takes place at the edge of the flange when the drawing ratio is up to 1.8. For the ECARed sheet, the fracture surface is smoothing and the cleavage fracture is presented, which is mainly related to the stress-strain status during the deep drawing and the sheet texture. These are ascribed to the difference of the texture in the two types of sheets, which is confirmed by uniaxial tensile tests and fracture morphology analysis of the two type of sheets.
参考文献
| [1] | Hans-Wilfried Wagener;Jorg Hosse-Hartmann;Reinhard Friz .Deep drawing and impact extrusion of magnesium alloys at room temperature[J].Advanced Engineering Materials,2003(4):237-242. |
| [2] | Kalidindi SR. .Modeling anisotropic strain hardening and deformation textures in low stacking fault energy fcc metals[J].International Journal of Plasticity,2001(6):837-860. |
| [3] | Poss R .Sheet metal production of magnesium[J].Materials Science Forum,2003,419-422:327-336. |
| [4] | Perez-Prado M T;Valle J A;Contreras J M et al.Microstructural evolution during large strain hot rolling of an AM60 Mg alloy[J].Scripta Materialia,2004,50:661-6665. |
| [5] | Valle J A;Prado M T;Ruano 0 A .Texture evolution during large-strain hot rolling of the AZ61 Mg alloy[J].Materials Science and Engineering,2003,A355:68-78. |
| [6] | M. Mabuchi;H. Iwasaki;K. Yanase;K. Higashi .LOW TEMPERATURE SUPERPLASTICITY IN AN AZ91 MAGNESIUM ALLOY PROCESSED BY ECAE[J].Scripta materialia,1997(6):681-686. |
| [7] | W.J. Kim;S.I. Hong;Y.S. Kim .Texture development and its effect on mechanical properties of an AZ61 Mg alloy fabricated by equal channel angular pressing[J].Acta materialia,2003(11):3293-3307. |
| [8] | Yu Yoshida;Lawrence Cisar;Shigeharu Kamado .Effect of Microstructural Factors on Tensile Properties of an ECAE-Processed AZ31 Magnesium Alloy[J].Materials transactions,2003(4):468-475. |
| [9] | J. Koike .New Deformation Mechanisms in Fine-Grain Mg Alloys[J].Materials Science Forum,2003(Pt.1):189-194. |
| [10] | Jin L;Lin DL;Mao DL;Zeng XQ;Chen B .Microstructure evolution of AZ31 Mg alloy during equal channel angular extrusion[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2006(1-2):247-252. |
| [11] | liY Y;Zhang D T;Chen W P et al.Microstructure evolution of AZ31 magnesium alloy during equal channel angular extrusion[J].Journal of Materlials Science,2004,39:3759-3761. |
| [12] | H.K. Kim;W.J. Kim .Microstructural instability and strength of an AZ31 Mg alloy after severe plastic deformation[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2004(1/2):300-308. |
| [13] | K. Iwanaga;H. Tashiro;H. Okamoto;K. Shimizu .Improvement of formability from room temperature to warm temperature in AZ-31 magnesium alloy[J].Journal of Materials Processing Technology,2004(0):1313-1316. |
| [14] | Chen Z H;Cheng Y Q;Xia W J .Effect of equal channel angular rolling pass on microstructure and properties of magnesium alloy sheets[J].Materials andManufacturing Processes,2007,22:51-556. |
| [15] | Z. H. Chen;Y. Q. Cheng;Z. H. Chen .Press Formability Of AZ31 Magnesium Alloy Sheets Produced By Equal Channel Angular Rolling[J].Materials Technology,2006(3):148-150. |
| [16] | Yong Qi Cheng;Zhen Hua Chen;Wei Jun Xia;Tao Zhou .Effect of channel clearance on crystal orientation development in AZ31 magnesium alloy sheet produced by equal channel angular rolling[J].Journal of Materials Processing Technology,2007(1/3):97-101. |
| [17] | Yong Qi Cheng;Zhen Hua Chen;Wei Jun Xia .Drawability of AZ31 magnesium alloy sheet produced by equal channel angular rolling at room temperature[J].Materials Characterization,2007(7):617-622. |
| [18] | Masahide Kohzu;Fusahito Yoshida;Kenji Higashi .Evaluation of Press Formability in Magnesium Alloy[J].Materials Science Forum,2003(Pt.1):321-326. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%