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The implantation of nitrogen ion is one of the important techniques for modifying the surface characteristics to improve wear and corrosion resistance of commercially pure (cp) Titanium. Although nitrogen ions implanted titanium in various dose demonstrated significant changes of the wear and corrosion resistance, the variable energy implanted is still not yet fully studied. Nitrogen ions were implanted in cp Titanium surface with varies of both dose of 0.5; 1.0 and 2.0 x1017 ions cm-2 and energy of 80, 100 and 115 keV. The nitrogen ion implanted cp Titanium demonstrated an increase in the surface hardness and improvement in corrosion behavior. The maximum surface hardness was delivered by the specimens implanted with the dose of 2.0x1017 ions cm-2 at energy of 80 keV. Grazing incidence x-ray diffraction studies indicated that TiN phase was formed on near surface substrate. Electrochemical tests in 3.5%-wt NaCl solution depicted significant improvements in corrosion resistance for specimens implanted with dose of 0.5x1017 and 1.0x1017 ions cm-2 at energy of 80 keV, dose of 1.0x1017 and 2.0x1017 ions cm-2 at energy of 100 keV. The dose of 2.0x1017 ions cm-2 and energy of 100 were the best implantation parameter in this study.

Prediction of fatigue life has become an interesting issue in biomaterial engineering and design for reliability and quality purposes, particularly for biometallic material with modified surfaces. Commercially pure titanium (Cp-Ti) implanted with nitrogen ions is a potential metallic biomaterial of the future. The effect of nitrogen ion implantation on fatigue behavior of Cp-Ti was investigated by means of axial loading conditions. The as-received and nitrogen-ion implanted specimens with the energy of 100 keV and dose of 2 × 10 17 ions cm -2 , were used to determine the fatigue properties and to predict the life cycle of the specimens. The effect of nitrogen ion implantation indicated revealed improved the tensile strength due to the formation of nitride phases, TiN and Ti 2 N. The fatigue strength of Cp-Ti and Nii-Ti was 250 and 260 MPa, respectively. The analytical results show good agreement with experimental results.

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Understanding the corrosion rate of metallic building materials is very important to maximize their beneficial use of public facilities. Direct measurements of the weight change and corrosion rate would be time consuming and expensive. This study aims to develop new empirical models based on the experimental data of testing 25 specimens immersed in five different environments for predicting the weight change and corrosion rate of the low-carbon steel. Using the equation developed based on the correlation between corrosion rate and chloride ion concentration is able to predict the corrosion rate of low-carbon steel at the limited chloride ion concentration. An increase in the trend lines of plotting the modeled and measured weight change of low-carbon steel versus immersion time is very similar to each other and progressively increase with increasing of the NaCl concentration. The corrosion rate of low-carbon steel increases from 0.202 to 0.286 mm/y with increasing of the NaCl concentration from 0 to 5% (w/w) in aqueous solution. The weight change and corrosion rate of the steel material are predicted using the new empirical models to contribute to the most reliable applications of low-carbon steel building materials in the future.