A criterion for evaluating glass-forming ability of alloys

Abstract

Articles you may be interested inTemperature dependence of the thermoplastic formability in bulk metallic glasses Abnormal behavior of supercooled liquid region in bulk-forming metallic glasses The correlation between shear elastic modulus and glass transition temperature of bulk metallic glasses Appl. Phys. Lett. 94, 091907 (2009); 10.1063/1.3093879 Noncontact measurement of high-temperature surface tension and viscosity of bulk metallic glass-forming alloys using the drop oscillation technique Appl. Phys. Lett. 86, 014104 (2005); 10.1063/1.1844596Overheating threshold and its effect on time-temperature-transformation diagrams of zirconium based bulk metallic glasses A criterion defined as = ͑T x + T g ͒ / T l ͓͑T x − T g ͒ / T l ͔ ␣ ͑where T x is the onset crystallization temperature, T g is the glass transition temperature, T l is liquidus temperature, and ␣ is an exponent͒ is proposed to evaluate the glass-forming ability of alloy systems. Regression analysis between the logarithm of the critical cooling rate ln R c and yields value of ␣ = 0.0728. There exists a fine linear relationship between criterion and ln R c with a coefficient of determination R 2 = 0.942. The obtained relationship can be expressed as: ln R c = ͑30.10Ϯ 0.91͒ − ͑27.93Ϯ 0.97͒ . The comparisons of with all other relevant parameters: ͕=T rg ͓͑T x − T g ͒ / T g ͔ 0.143 ͖, ␥͓=T x / ͑T l + T g ͔͒, T rg ͑=T g / T l ͒, ␤͓=T x T g / ͑T l − T x ͒ 2 ͔, ␦͓=T x / ͑T l − T g ͔͒ show that this criterion has the best ability for evaluating the GFA of alloys.

Which glass stability parameters can assess the glass‐forming ability of oxide systems?

“…[24]* 2 = ( − )( − ) [33] ∆ = − [24] ( ) = + [34] ( ) = + [34] ∆ = − [35] = + [36] = − [14] = ( ∆ ) 0.143 [15] = 2 − [16] = + [17] [22] = + ( − ) 0,0728 [23] = 3 − 2 [25] 2 = − 1.3 [26] = − − [27] = ( − ) ( − ) 2 [28] = ( − ) 2 [29] *Variation of other original equation, ** Cited in this reference without informing the source.…”

“…The Kw = (Tc−Tg)/Tl parameter, proposed by Weinberg, includes a normalization by Tl [23] of the Tg (Tc) = Tc−Tg parameter, which is taken by several authors as a measure of glass stability, e.g. [17,31].…”

High-Throughput Synthesis and Characterization Screening of Mg-Cu-Y Metallic Glass

“…Many of the most popular criteria are based on calculations from characteristic temperatures. However, these temperatures are determined experimentally using differential scanning calorimetry (DSC) [4,[11][12][13][14][15][16][17][18][19][20][21][22]. Dozens of criteria have been proposed [10], but the most notable of these are the reduced glass transition temperature T rg , which is the ratio between the liquidus T l and glass transition T g temperatures (T rg = T l /T g ) [11]; the supercooled liquid temperature range, that is the difference between T g and the onset of the first crystallization peak, T x (∆T x = T x − T g ) [4]; and the parameter γ = T g /(T x + T l ) [12].…”

Электрическое сопротивление и магнитная восприимчивость сплавов CoFeSiBNb + REM при высоких температурах

“…Одним из недостатков этих материалов, сдерживающим широкое применение, является относительно низкая стеклообразующая способность (glass-forming ability -GFA) [3]. Способам расчета GFA посвящено много работ [4][5][6][7][8]. К сожалению, существующие на сегодняшний день критерии GFA не обладают предсказательной функцией.…”