Effect of low-energy proton on the microstructure, martensitic transformation and mechanical properties of irradiated Ni-rich TiNi alloy thin films

A new methodology using very low energy Ar ion irradiation is proposed to improve the mechanical properties of thin metal films deposited by sputtering. In this study, accelerating voltage of Ar ion plasma was set to lower than 100V, and several conditions were applied to irradiations. Consequently, it is found that Young’s modulus and hardness of Aluminum and Nickel thin film increases about 10% by the irradiation compared with a non-irradiated thin film. (111)–oriented integrated intensity of diffraction of Al and Ni thin film was increased by the irradiation. It is considered that crystalline orientation was changed and column spacing of the film be filled by the irradiation. It is shown that the proposed technique is effective to improve the mechanical properties of metal thin films with proper irradiation conditions.

Download Full-text

Influence of low energy ion implantation on mechanical properties of magnetron sputtered metastable (Cr,Al)N thin films

Thin Solid Films ◽

10.1016/s0040-6090(03)00595-9 ◽

2003 ◽

Vol 437 (1-2) ◽

pp. 164-169 ◽

Cited By ~ 51

Author(s):

S Ulrich ◽

H Holleck ◽

J Ye ◽

H Leiste ◽

R Loos ◽

...

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Ion Implantation ◽

Low Energy

Download Full-text

Mechanical twinning and subgrain formation in ordered Ti50Ni47Fe3

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105151 ◽

1988 ◽

Vol 46 ◽

pp. 618-619

Author(s):

W. J. Moberly

Keyword(s):

Mechanical Properties ◽

Martensitic Transformation ◽

Room Temperature ◽

Cold Working ◽

Thermomechanical Processing ◽

Mechanical Twinning ◽

Deformation Mechanisms ◽

Tini Alloy ◽

Recovery Annealing ◽

Subgrain Formation

TiNi is an intermetallic compound with the B2(CsCl) crystal structure. As temperature decreases, it undergoes a martensitic transformation from cubic B2 to monoclinic B19', the reversibility of which is responsible for shape memory properties. Ordered intermetallics generally have limited ductilty, however, >50% elongation of TiNi has been produced by either warm or cold working. Consequently, thermomechanical processing has resulted in improved mechanical properties. TEM is required to characterize the deformation mechanisms (mechanical twinning and slip) and resulting substructures.Substitution of 3%Fe for Ni into the binary TiNi alloy (Ti50Ni47Fe3) depresses the martensitic transformation, such that room temperature working does not stress induce the martensitic transformation. In order to improve the mechanical properties of this B2 intermetallic, fully annealed (875°C/2 hrs) bars have been cold swaged 10%,20%,30% and 40%, followed by different recovery annealing treatments. Additional samples have been warm swaged at 500°C. The structure is observed optically and by TEM, utilizing Philips' EM 400 twin and EM 430 super twin microscopes.

Download Full-text