Development of spinal implant Development of spinal implant rod made of Ti-29Nb-13Ta-rod made of Ti-29Nb-13Ta-
4.6Zr4.6Zr
Spinal fixationSpinal fixation
Plug
Rod
Screw
Fig. The spinal fixation method for treatment of scoliosis, a) picture of women with scoliosis ,b) X-Ray of Curve before surgery, c) Fixation during surgery, d)X-Ray after surgery
a) b) c) d)
Collaborative projectCollaborative project
Showa Ika
Kogyo Co., Ltd
Project managementPatent standerd
America(Dr.
Burger)
TohokuUniversi
tyBasic study
Europe(Prof. Steib)
Comments and needsAnimal experiment
Medical doctors
Study in Tohoku Univ.Study in Tohoku Univ.
500
600
700
800
900
Ma
xim
um
Cyc
lic S
tre
ss,σ
ma
x/M
Pa
Fig. S-N curves of Ti-29Nb-13Ta-4.6 subjected to various thermo-mechanical treatment in air.
Number of Cycles to Failure , Nf
105 106 107104103 108
1000
1100
Improvement of fatigue propertyProcess 1Solution treatment → aging treatmentProcess 2Cold rolling → aging treatmentProcess 3Swaging → aging treatment
Ti64 rod(Conventional material of implant rod)