Temperature measurement using a Chx/porous silicon/Si structure encapsulated in a CO2 rich environment
This work reports on the possible use of microporous silicon as a temperature sensor. This work is based on previous published works [7, 8, and 9]. The device is based on hydrocarbon group (CHx) / porous silicon (PS) /Si structure. The porous sample was coated with hydrocarbons groups deposited by the plasma of methane /argon mixture. Current-voltage characteristics have been investigated as a function of temperature in the range 20°C-70°C. The results show that for a constant voltage in the range 0.7-1V, the current increases linearly with the environment temperature reaches a maximum at 70°C and then stabilizes. This result suggests that the developed structure can be used for sensing temperatures not exceeding 70°C.
Failure analysis of the exhaust valve face in diesel marine engine
The exhaust valve from marine diesel engine which was damaged after 2000 hours of service was investigated. In order to prolong the service time the valve face was cladded with cobalt base alloy using laser technique. After failure microstructural and chemical analyses reviled that cladding process was conducted improperly. The chemical composition of the clad layer was far from the designed one and what more completely inhomogeneous. As a result the valve presented different properties in different regions which led to premature failure.
Optimal Features of Porosity of Ti Alloys Considering their Bioactivity and Mechanical Properties
This article reviews the influence of porosity and pore sizes of titanium and titanium alloys, used as orthopaedic materials, on bioactivity and mechanical properties of the porous structures. The optimal features of porous titanium scaffolds allow the reconstruction and regeneration of bone tissue in load-bearing applications.
Temperature measurement using a Chx/porous silicon/Si structure encapsulated in a CO2 rich environment
This work reports on the possible use of microporous silicon as a temperature sensor. This work is based on previous published works [7, 8, and 9]. The device is based on hydrocarbon group (CHx) / porous silicon (PS) /Si structure. The porous sample was coated with hydrocarbons groups deposited by the plasma of methane /argon mixture. Current-voltage characteristics have been investigated as a function of temperature in the range 20°C-70°C. The results show that for a constant voltage in the range 0.7-1V, the current increases linearly with the environment temperature reaches a maximum at 70°C and then stabilizes. This result suggests that the developed structure can be used for sensing temperatures not exceeding 70°C.
Failure analysis of the exhaust valve face in diesel marine engine
The exhaust valve from marine diesel engine which was damaged after 2000 hours of service was investigated. In order to prolong the service time the valve face was cladded with cobalt base alloy using laser technique. After failure microstructural and chemical analyses reviled that cladding process was conducted improperly. The chemical composition of the clad layer was far from the designed one and what more completely inhomogeneous. As a result the valve presented different properties in different regions which led to premature failure.
Optimal Features of Porosity of Ti Alloys Considering their Bioactivity and Mechanical Properties
This article reviews the influence of porosity and pore sizes of titanium and titanium alloys, used as orthopaedic materials, on bioactivity and mechanical properties of the porous structures. The optimal features of porous titanium scaffolds allow the reconstruction and regeneration of bone tissue in load-bearing applications.