The alpha-case formation reactions between Ti and investment molds (Al-2O-3,ZrSiO-4,ZrO-2,CaO stabilized ZrO-2) were evaluated in a plasma arc melting furnace.Regardless of thermodynamic approaches,there were distin...The alpha-case formation reactions between Ti and investment molds (Al-2O-3,ZrSiO-4,ZrO-2,CaO stabilized ZrO-2) were evaluated in a plasma arc melting furnace.Regardless of thermodynamic approaches,there were distinct alpha-case formations.The reaction products were characterized by electron probe micro-analysis and transmission electron microscopy.Theα-case generation between Ti and Al-2O-3 mold was not able to be explained by the conventionalα-case formation mechanism,which is known to be formed by the interstitials,especially oxygen dissolved from mold materials.However,from our experimental results and thermodynamic calculations,it was confirmed that theα-case is formed not only by an interstitial element but also by substitutional metallic elements dissolved from mold materials.Our newly establishedα-case formation mechanism will surely lead to a variety of significant applications of theα-case controlled Ti casting.展开更多
The main purpose of this study is an in-situ synthesis of (TiB+TiC) hybrid titanium matrix composites (TMCs) by vacuum induction melting method and to verify its mechanical properties.The melting route was adopte...The main purpose of this study is an in-situ synthesis of (TiB+TiC) hybrid titanium matrix composites (TMCs) by vacuum induction melting method and to verify its mechanical properties.The melting route was adopted to synthesize the commercial pure titanium (cp Ti) and granular boron carbide (B-4C).The reinforcements,the fraction of 10 vol.pct,were formed by adding 1.88 wt pct B-4C to cp Ti.After in-situ synthesis of TMCs,electron probe micro-analysis elemental mapping was carried out to confirm the distribution and shape of reinforcements.The cone-on-disk type sliding wear test was also done for the identification of TMCs.It is concluded that (TiB+TiC) hybrid TMCs can be in-situ synthesized and has better wear properties than H13.展开更多
文摘The alpha-case formation reactions between Ti and investment molds (Al-2O-3,ZrSiO-4,ZrO-2,CaO stabilized ZrO-2) were evaluated in a plasma arc melting furnace.Regardless of thermodynamic approaches,there were distinct alpha-case formations.The reaction products were characterized by electron probe micro-analysis and transmission electron microscopy.Theα-case generation between Ti and Al-2O-3 mold was not able to be explained by the conventionalα-case formation mechanism,which is known to be formed by the interstitials,especially oxygen dissolved from mold materials.However,from our experimental results and thermodynamic calculations,it was confirmed that theα-case is formed not only by an interstitial element but also by substitutional metallic elements dissolved from mold materials.Our newly establishedα-case formation mechanism will surely lead to a variety of significant applications of theα-case controlled Ti casting.
文摘The main purpose of this study is an in-situ synthesis of (TiB+TiC) hybrid titanium matrix composites (TMCs) by vacuum induction melting method and to verify its mechanical properties.The melting route was adopted to synthesize the commercial pure titanium (cp Ti) and granular boron carbide (B-4C).The reinforcements,the fraction of 10 vol.pct,were formed by adding 1.88 wt pct B-4C to cp Ti.After in-situ synthesis of TMCs,electron probe micro-analysis elemental mapping was carried out to confirm the distribution and shape of reinforcements.The cone-on-disk type sliding wear test was also done for the identification of TMCs.It is concluded that (TiB+TiC) hybrid TMCs can be in-situ synthesized and has better wear properties than H13.