scholarly journals Unlubricated Sliding Properties of Ion Beam and Excimer Laser Mixed Fe-Ti-C Multilayered Films

1988 ◽  
Vol 140 ◽  
Author(s):  
J-P. Hirvonen ◽  
M. Nastasi ◽  
T.R. Jervis ◽  
J.R. Tesmer ◽  
T.G. Zocco

AbstractMultilayered Fe-Ti-C films consisting of eleven sublayers were vacuum deposited onto an AISI 304 stainless steel substrate and subsequently mixed using either 400 keV Xe ions or an excimer laser operating at a wavelength of 308 nm. Ion mixing was accomplished in a two step process: the multilayers were first irradiated with 1xl017 Xe/cm2 at 520 °C, after which half of the sample was irradiated with 5x1015 Xe/cm2 at 0 °C. Laser mixing was carried out at both 1.1 and 1.7 J/cm17 with the number of pulses varied between 1 and 10. Pin-on-disc studies revealed only slight differences between the two kinds of ion beam mixed samples, whereas the dry sliding properties of laser mixed samples were strongly dependent on the total fluence used. In the optimum conditions, similar friction coefficients were obtained on both kinds of samples.

1988 ◽  
Vol 128 ◽  
Author(s):  
J-P. Hirvonen ◽  
M. Nastasi ◽  
T. R. Jervis ◽  
J. R. Tesmer ◽  
T.G. Zocco

ABSTRACTMultilayered Fe-Ti-C films consisting of eleven sublayers were vacuum deposited onto an AISI 304 stainless steel substrate and subsequently mixed using either 400 key Xe ions or an excimer laser operating at a wavelength of 308 nm. Ion mixing was accomplished in a two step process: the multilayers were first irradiated with 1×1017 Xe/cm2 at 520°C, after which half of the sample was irradiated with 5×1015 Xe/cm2 at 0 °C. Laser mixing was carried out at both i.i and 1.7 J/cm2 with the number of pulses varied between 1 and 10. Pin-on-disc studies revealed only slight differences between the two kinds of ion beam mixed samples, whereas the dry sliding properties of laser mixed samples were strongly dependent on the total fluence used. In the optimum conditions, similar friction coefficients were obtained on both kinds of samples.


1987 ◽  
Vol 93 ◽  
Author(s):  
G.-P. Hirvonen ◽  
M. Nastasi ◽  
J. W. Mayer

ABSTRACTA surface layer of Fe50Ti50 on AISI 304 stainless steel was produced by ion beam mixing a Fe-Ti multilayer structure. Subsequently, the layer was implanted with C, N, or C+N ions. The dry sliding properties of these surfaces were tested using a ceramic pin as a rider in pin-on-disc measurements. Implantations produced significant improvements in the surface friction and wear properties. Samples implanted with C or C+N showed good tribological properties even under conditions where the Herzian peak pressure exceeded the yield strength of the substrate. As a result of different treatments the appearance of the wear tracks examined with a scanning electron microscope was also changed.


Respuestas ◽  
2018 ◽  
Vol 23 (1) ◽  
pp. 6
Author(s):  
Alfonso Santos Jaimes ◽  
Zulma Yainell Ramírez Jaimes ◽  
Carlos Gerardo Cárdenas Arias ◽  
Emil Hernández Arroyo

 En este artículo se presentan los resultados de la investigación relacionada con el comportamiento experimental de recubrimientos de alúmina, obtenidos a partir de partículas de tamaño micrométrico y depositadas a través de un proceso de rociado térmico por llama, sobre un sustrato de acero inoxidable AISI 304, cuando están sometidos a desgate erosivo originado por cavitación a través de un aparato vibratorio. La metodología utilizada para alcanzar el objetivo propuesto consistió de cinco fases, en la primera se realizó una caracterización morfológica y química de los materiales utilizados; la segunda fue la adaptación del equipo de ultrasonido UIP1000hd a los requerimientos exigidos por la norma ASTM G32-16 (Método de pruebas estándar para erosión por cavitación usando aparatos vibratorios); posteriormente se ensayaron probetas de acero inoxidable AISI 304 para comprobar el funcionamiento del equipo utilizado, la validación del fenómeno de desgaste presente en las probetas se realizó a través de ensayos de microscopia electrónica de barrido con el fin de observar la evolución de la huella dejada sobre el espécimen; como cuarta fase se realizó la deposición de los recubrimientos de alúmina a través de un equipo de combustión oxiacetilénica convencional y una pistola Eutalloy 85 BX; por último se realizaron ensayos de microdureza y resistencia al desgaste erosivo a probetas de acero inoxidable AISI 304 sin y con recubrimientos de alúmina. Los resultados obtenidos permitieron validar el funcionamiento del equipo adaptado para la realización de los ensayos ya que el porcentaje de error promedio entre los datos experimentales y teóricos fue del 4,5% para el acero inoxidable AISI 304; respecto al comportamiento de los recubrimientos de alúmina se obtuvo una reducción del 26,23% de pérdida de material con respecto al acero inoxidable AISI 304, lo que representa una mejora significativa e incentiva su utilización cuando se tienen elementos mecánicos sometidos a desgaste erosivo originado por cavitación. Palabras clave: Alúmina, Desgaste, Erosión, Recubrimientos. AbstractThis article presents the results of the research related to the experimental behavior of alumina coatings obtained from micrometric size particles and deposited through a thermal spraying by flame process on an AISI 304 stainless steel substrate when it is subjected to erosive wear caused by cavitation through a vibratory apparatus. The methodology used to reach the proposed objective consisted of five phases in the first a morphological and chemical characterization of the materials used, was carried out; the second was the adaptation of UIP1000hd ultrasound equipment to the requirements demanded by the ASTM G32-16 standard (standard test method for erosion by cavitation using vibrating apparatus); afterwards, test pieces of AISI 304 stainless steel were tested to verify the performance of the equipment used, the validation of the wear phenomenon present in the specimens was carried out through scanning electron microscopy tests in order to observe the evolution of the footprint left over the specimen; as a fourth phase, the deposition of the alumina coatings was carried out through a conventional oxyacetylene combustion equipment and an Eutalloy 85 BX gun; finally micro-hardness and erosive wear resistance tests were carried out on AISI 304 stainless steel specimens without and with alumina coatings. The results obtained allowed to validate the operation of the adapted equipment for the performance of the tests since the percentage of average error between the experimental and theoretical data was of 4,5% for AISI 304 stainless steel; regarding the behavior of alumina coatings a 26,23% reduction of material loss was obtained with respect to the AISI 304 stainless steel which represents a significant improvement and encourages its use when mechanical elements are subjected to erosive wear caused by cavitation. Keywords: Alumina, Wearing away, Erosion, Coatings. ResumoEste artigo apresenta os resultados da pesquisa relacionada ao comportamento experimental de revestimentos de alumina, obtidos a partir de partículas micrométricas e depositados através de um processo de chama térmica, sobre um substrato de aço inoxidável AISI 304, quando submetido a erosão erosiva causada por cavitação através de um aparelho vibratório. A metodologia utilizada para atingir o objetivo proposto consistiu de cinco fases, sendo que na primeira foi realizada uma caracterização morfológica e química dos materiais utilizados; o segundo foi a adaptação do equipamento de ultra-som UIP1000hd aos requisitos exigidos pela norma ASTM G32-16 (método de teste padrão para erosão por cavitação utilizando aparelhos vibratórios); subsequentemente, eles espécimes aço inoxidável AISI 304 foram testadas para a operação do equipamento utilizado, a validação de fenómeno de desgaste presente nas amostras foi realizada por meio de testes de microscopia electrónica de varrimento a fim de observar a evolução da marca deixada sobre o espécime; como uma quarta fase, a deposição dos revestimentos de alumina foi realizada através de equipamento de combustão de oxiacetileno convencional e uma pistola Eutalloy 85 BX; Finalmente, testes de microdureza e resistência à erosão foram realizados em amostras de aço inoxidável AISI 304 sem e com revestimentos de alumina. Os resultados obtidos permitiram validar a operação do equipamento adaptado para a realização dos ensaios, uma vez que a porcentagem de erro médio entre os dados experimentais e teóricos foi de 4,5% para o aço inoxidável AISI 304; sobre o comportamento dos revestimentos de alumina redução de 26,23% de perda de material em comparação com o aço inoxidável AISI 304 foi obtido, o que representa uma melhoria significativa e encoraja a utilização quando os elementos mecânicos são submetidos a erosiva desgaste causado pela cavitação.Palavras-chave:  Alumina, Desgastando, Erosão, Revestimentos.


Entropy ◽  
2018 ◽  
Vol 21 (1) ◽  
pp. 2 ◽  
Author(s):  
Wenyuan Cui ◽  
Sreekar Karnati ◽  
Xinchang Zhang ◽  
Elizabeth Burns ◽  
Frank Liou

Through laser metal deposition, attempts were made to coat AlCoCrFeNi, a high-entropy alloy (HEA), on an AISI 304 stainless steel substrate to integrate their properties. However, the direct coating of the AlCoCrFeNi HEA on the AISI 304 substrate was found to be unviable due to cracks at the interface between these two materials. The difference in compositional change was suspected to be the source of the cracks. Therefore, a new transition route was performed by coating an intermediate layer of CoFe2Ni on the AISI 304 substrate. Investigations into the microstructure, phase composition, elemental composition and Vickers hardness were carried out in this study. Consistent metallurgical bonding was observed along both of the interfaces. It was found that the AlCoCrFeNi alloy solidified into a dendritic microstructure. The X-ray diffraction pattern revealed a transition of the crystal structure of the AISI 304 substrate to the AlCoCrFeNi HEA. An intermediate step in hardness was observed between the AISI 304 substrate and the AlCoCrFeNi HEA. The AlCoCrFeNi alloy fabricated was found to have an average hardness of 418 HV, while the CoFe2Ni intermediate layer had an average hardness of 275 HV.


1988 ◽  
Vol 3 (6) ◽  
pp. 1104-1107 ◽  
Author(s):  
T. R. Jervis ◽  
J. -P. Hirvonen ◽  
M. Nastasi

Dry sliding friction measurements made on titanium layers evaporated on AISI 304 stainless steel in the as-deposited and excimer laser mixed form show a dependence on the film thickness and the amount of mixing. The effect of laser mixing is dependent on the incident fluence with high fluences and/or large numbers of pulses producing surfaces with poor frictional properties. The optimum total fluence depends on the thickness of the surface layer, a result consistent with thorough mixing of the alloyed layer without the surface damage that results from large numbers of pulses.


1988 ◽  
Vol 128 ◽  
Author(s):  
T. R. Jervis ◽  
J-P. Hirvonen ◽  
M. Nastasi ◽  
T. G. Zocco ◽  
J. A. Martin ◽  
...  

ABSTRACTWe have investigated the properties of surface alloys of Ti formed by excimer laser melting and mixing of Ti overlayers on AISI 304 stainless steel substrates.The thickness of the initial Ti surface layers and the fluence and number of pulses used to mix the surface were varied to investigate a broad range of processing conditions. Samples were uniformly translated at different speeds under repetitive pulses of homogenized laser radiation at 308 nm to vary the number of pulses incident on the sample. We investigated the surface structure and composition, the wear and friction behavior, and the surface hardness of the resulting alloys.The extent of mixing is observed by Rutherford backscattering spectroscopy to be proportional to the number of pulses incident on the sample. Amorphous surface layers are formed at some mixing levels with a composition which indicates that Ti substitutes for Fe in the stainless steel on a one to one basis. Incorporation of C from surface and interface contamination is observed but at a level much below that found in comparable ion implanted materials.Friction coefficient measurements indicate that there exists an optimum level of mixing for each layer thickness. Excessive mixing degrades both the coefficient of friction and the wear performance in dry sliding tests.As with the tribological measurements, the surface hardness showed a dependence on amount of mixing. The surface hardness of the as deposited samples was higher than that of the laser mixed samples, initially decreased with mixing, and finally increased with further mixing.


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