Deformation induced primary crystallization in a thermally non-primary crystallizing amorphous Al85Ce8Ni5Co2 alloy

Cold Consolidation of Ball-Milled Titanium Powders Using High-Pressure Torsion

“…[3] In the HPT process, first introduced by Bridgman in 1935, [4] a small thin disc is placed between two massive anvils under a high hydrostatic pressure and intense shear strain is introduced by rotating the two anvils with respect to each other. The HPT as a processing tool for consolidation of powders was first used in 1991 [2] and further developed for the consolidation of metallic powders, [5][6][7][8] composites, [9][10][11][12][13][14][15][16][17][18][19][20][21][22] amorphous compounds, [22][23][24][25][26][27][28] machining chips, [28][29][30] and very recently for ceramic powders. [31] The HPT process was also applied successfully as a cold consolidation technique without sintering process for ball-milled powders including pure Ni, [5] pure Co, [7] an Al-Mg alloy, [8] Co-based metal-ceramic composites, [17,18] and amorphous powders and chips.…”

High-Pressure Torsion of Machining Chips and Bulk Discs of Amorphous Zr<SUB>50</SUB>Cu<SUB>30</SUB>Al<SUB>10</SUB>Ni<SUB>10</SUB>

“…[3][4][5][6][7][8][9][10][11][12][13][14][15] The application includes the consolidation of metallic powders, [3][4][5] composites, [6][7][8][9][10][11][12] ball-milled powders, 13,14) amorphous powders, 15) amorphous ribbons, 16) and very recently machining chips. 17,18) Strain-induced amorphization was reported for some compounds, 19,20) whereas crystallization is detected in amorphous materials such as Cu 50 [21][22][23][24][25][26][27][28][29][30][31] It is well established that bulk amorphous materials have high strengths and high hardness [32][33][34][35] and it is known that processing through HPT leads to an increase in the strength of metallic materials. 1,<...>…”

“…17,18) Strain-induced amorphization was reported for some compounds, 19,20) whereas crystallization is detected in amorphous materials such as Cu 50 [21][22][23][24][25][26][27][28][29][30][31] It is well established that bulk amorphous materials have high strengths and high hardness [32][33][34][35] and it is known that processing through HPT leads to an increase in the strength of metallic materials. 1,2) In spite of many publications regarding the HPT processing of amorphous materials, [21][22][23][24][25][26][27][28][29][30][31] little attention has been paid to the strength of amorphous materials after processing by HPT.…”

Microstructure and properties of cold consolidated amorphous ribbons from (NiCu)ZrTiAlSi alloys

“…The microstructure produced by HPT is basically metastable, and may relax [8]. In case of the amorphous materials the method was applied to produce massive samples from the melt-spun ribbons by consolidation at room temperature [9][10][11]. This application is especially interesting for the amorphous alloys relatively easy to achieve with melt spinning methods but hard to prepare in the form of the bulk amorphous samples.…”

“…This application is especially interesting for the amorphous alloys relatively easy to achieve with melt spinning methods but hard to prepare in the form of the bulk amorphous samples. However it was commonly observed that the large strains in HPT induce crystallization in the amorphous matrix [9][10][11] which was considered to be athermal in nature [12]. The crystallization induced by HPT reveals the dependence of the distance on the rotation axis, and on the range of the accumulated shear strain.…”