The dependence of lamellar spacings and microhardness on the growth rate in the directionally solidified Bi-43 wt.% Sn alloy at a constant temperature gradient

Sn – Cd eutectic melt was first obtained in a hot filling furnace and then directionally solidified upward with different growth rate ranges (8.1–165 μm/s) at a constant temperature gradient G (4.35 K/mm) in the Bridgman-type directional solidification furnace. The lamellar spacings (λ) were measured from both transverse and longitudinal sections of the samples. The influence of the growth rate (V) on lamellar spacings (λ) and undercoolings (Δ T) was analyzed. λ2V, ΔTλ and ΔTV-0.5 values were determined by using λ,ΔT and V values. Microindentation hardness (HV) was measured from both transverse and longitudinal sections of the specimens. HV values increase with the increasing values of V but decrease with increasing λ values. λ-V, λ - ΔT and λ2V results have been compared with the Jackson–Hunt eutectic model and similar experimental results, HV - V and HV - λ results were also compared with the previous work.

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Influence of Growth Rate on the Solute Distribution of Directionally Solidified Cu-Ag-Zr Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.275.192 ◽

2011 ◽

Vol 275 ◽

pp. 192-195

Author(s):

Bok Hyun Kang ◽

Woo Hyun Lee ◽

Ki Young Kim ◽

Hoon Cho ◽

Jae Soo Noh

Keyword(s):

Electrical Conductivity ◽

Growth Rate ◽

Temperature Gradient ◽

Constant Temperature ◽

Vickers Hardness ◽

Growth Rates ◽

Back Diffusion ◽

Directionally Solidified ◽

Constant Temperature Gradient ◽

Zr Alloy

Cu-2wt.Ag-2wt.%Zr alloy was directionally solidified with different growth rates(V=10-200 um/s) at a constant temperature gradient(G=3.1 K/mm) in a modified Bridgman furnace. The influence of growth rate was investigated by observing the microstructure and measuring the solutes’ compositions within the Cu-matrix and dendrite boundaries. The experimental results show that increasing the growth rate, decreased both the primary and secondary arm spacing and increased micro-Vickers hardness. The solutes’ concentration also increased as a result of the back diffusion caused by a decreasing growth rate. The electrical conductivity depends on the solutes’ distribution.

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Microstructural Evolution and Mechanical Properties in Directionally Solidified Sn–10.2 Sb Peritectic Alloy at a Constant Temperature Gradient

Materials Research ◽

10.1590/1980-5373-mr-2015-0104 ◽

2016 ◽

Vol 19 (2) ◽

pp. 370-378 ◽

Cited By ~ 10

Author(s):

Elif Yılmaz ◽

Emin Çadırlı ◽

Emine Acer ◽

Mehmet Gündüz

Keyword(s):

Mechanical Properties ◽

Temperature Gradient ◽

Constant Temperature ◽

Microstructural Evolution ◽

Directionally Solidified ◽

Peritectic Alloy ◽

Constant Temperature Gradient

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Morphological Characteristics of W-Nanowires after Selective Etching

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1004-1005.24 ◽

2014 ◽

Vol 1004-1005 ◽

pp. 24-27

Author(s):

Wen Jia Wang ◽

Zhi Long Zhao ◽

Ming Tang ◽

Jian Jun Gao

Keyword(s):

Growth Rate ◽

Temperature Gradient ◽

Directional Solidification ◽

Morphological Characteristics ◽

Selective Dissolution ◽

Stability Diagram ◽

Selective Etching ◽

Directionally Solidified ◽

Solidification Furnace ◽

Nial Matrix

An eutectic NiAl–1.5 at.% W alloy prepared by using directionally solidified (DS)was employed as a source for producing W-nanowires. Several growth rate of 8,15,25/s was respectively used at a temperature gradient of ~240 K/cm in a Bridgman-type directional solidification furnace. A combined stability diagram was applied to predict proper conditions for the selective dissolution of NiAl matrix to get W-wires. Etching in a mixture of HCl:H2O2released parallel aligned W-nanowires with a wire diameter of ~500 nm. Different morphologies, such as nanobelts, lotus-shaped, conical of W-nanowires are obtained at the different conditions.

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