文章信息/Info

Title:

Study on the Surface Forming Quality of FeMnSi/NiTiNb Composite Pipe by Rotary Extrusion

文章編號:

1674-3962(2025)08-0785-08

作者:

宋思楠; 賈雄飛; 孫志超

西北工業大學材料學院，陜西 西安 710072

Author(s):

SONG Sinan;  JIA Xiongfei;  SUN Zhichao

School of Materials Science and Engineering,Northwestern Polytechnical University，Xi’an 710072, China

關鍵詞:

復合管; 旋轉擠壓; 數值模擬; 工藝參數; 變形模式

Keywords:

composite pipe;  rotary extrusion;  numerical simulation;  process parameters;  deformation mode

分類號:

TG139+.6；TG306

DOI:

10.7502/j.issn.1674-3962.202403024

文獻標志碼:

A

摘要:

旋轉擠壓工藝為鎳基/鐵基形狀記憶合金復合管成形提供了可能的新途徑，但由于兩種材料強度、塑性等差異較大，成形過程中容易出現變形不協調和不均勻，導致界面流速差大、分層等問題。為此設計了3種變形模式，通過有限元模擬研究了坯料溫度、擠壓比和模具角度對復合管旋轉擠壓界面成形質量關鍵指標——界面流動速度差和徑向壓應力的影響規律。發現：隨著坯料溫度、擠壓比和模具角度的增大，3種變形模式下的界面流動速度差均呈現增大趨勢；隨著坯料溫度的降低和擠壓比的增大，3種變形模式的徑向壓應力均呈現增大趨勢；隨著模具角度的增大，內定外縮和內擴外縮模式的徑向壓應力呈現減小趨勢，而整體縮徑模式的徑向壓應力卻呈現增大趨勢；綜合比較后確定了旋轉擠壓合理的變形模式：內擴外縮模式。

Abstract:

The rotary extrusion process provides a possible new way for forming Ni�瞓ased Fe-based shape-memory alloy composite pipes. However, due to the large differences in strength and plasticity between the two materials, during the forming process, the deformation is not harmonious and non-uniform,which leads to the problems of large flow velocity difference and delamination at the composite pipe interface. For this reason, this paper designed three deformation modes, the effects of billet temperature, extrusion ratio and die angle on the flow velocity difference and radial compressive stress were studied by finite element simulation. It is found that the differences of interfacial flow velocity under the three deformation modes increase with the increase of billet temperature, extrusion ratio and die angle; with the decrease of billet temperature and the increase of extrusion ratio, the radial compressive stresses increase; with the increase of die angle, the radial compressive stresses under the internal fixing and external reduction mode and the internal expansion and external reduction mode show a decreasing trend, however, the radial compressive stress under the overall reduction mode shows an increasing trend. Then the reasonable deformation mode of the rotary extrusion is determined: the internal expansion and external reduction mode.