Preparation and Characterization of V_3(Si,N) and V_3(Si,C) System Superconductors
| Project/Area Number |
61550533
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
金属材料(含表面処理・腐食防食)
|
|---|
| Research Institution | OSAKA UNIVERSITY |
|---|
Principal Investigator |
SAJI Shigeoki Faculty of Enginieering, Associate Professor, 工学部, 助教授 (60029072)
|
|---|
| Project Period (FY) |
1986 – 1987
|
| Project Status |
Completed (Fiscal Year 1987)
|
| Budget Amount *help |
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1987: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1986: ¥1,600,000 (Direct Cost: ¥1,600,000)
|
|---|
| Keywords | V_3 phase superconductor / V_3(Si,B) phase / low pressure gas plasma melting method / transition temperature / lattice parameter / 規則度 / 【V_3】Si系超電導化合物 / 窒素添加 / 炭素添加 / ボロン添加、臨界温度の向上 / 格子定数の低下 |
|---|
| Research Abstract |
V_3(Si,N), V_3(Si,B) compounds were attempted to be prepared by a low pressure gas plasma melting method. Compounds consisting of one fo V_3Si, V_3(Si,C) and V_3(Si,B) phases could be obtained by the above mentioned method.
The dependence of the normal-superconducting transition temperature, Tc on silicon concentration in the V_3Si and V_3(Si,B) phases has been investigated in the connection with lattice parameter and with degree of order of A-15 type of structure. Both T_c and degree of order decrease and lattice parameter increases linearly with decreasing silicon concentration in V_3Si and V_3(Si,B) phases from the stoichiometry to about 19 at % Si. The increase in the lattice parameter causee drop in T_c due to the decrease in Debye temperature, and the decrease in the degree of order causes drop in T_c due to the decrease in the electron density of states at ferumi surface.
Addition of about 0.5 at% boron to the V_3 Si phase brings about rise in T_c by 1-5 K in the range from 25 to 19 at% Si. The amount of the rise in T_c is about 1 K at the stoichiometry and reaches to about 5 K at 19 at% Si. The rise of T_c by addition of small amount of boron is mainly due to the decrease in lattice parameter of A-15 type of structure.
|
Report
(2 results)
Research Products
(5 results)
