Sintered Steel
Mostrando 13-24 de 28 artigos, teses e dissertações.
-
13. Strain hardening behaviour in forming of sintered iron-0.35% carbon powder metallurgy preform during cold upsetting
A complete experimental investigation on the instantaneous strain-hardening behaviour of powder metallurgy preforms of Fe-0.35%C was carried out. The strain hardening behaviour of the above-mentioned P/M sintered steel preforms with aspect ratio of 0.4 and 0.6, respectively, under triaxial stress state condition was determined by cold upsetting under nil/no
Materials Research. Publicado em: 28/10/2011
-
14. Porous stainless steel for biomedical applications
Porous 316L austenitic stainless steel was synthesized by powder metallurgy with relative density of 0.50 and 0.30 using 15 and 30 wt. (%) respectively of ammonium carbonate and ammonium bicarbonate as foaming agents. The powders were mixed in a planetary ball mill at 60 rpm for 10 minutes. The samples were uniaxially pressed at 287 MPa and subsequently vacu
Materials Research. Publicado em: 15/04/2011
-
15. Performance evaluation of carbide tools on automotive valve guides reaming / Avaliação do desempenho de ferramentas de metal duro no alargamento de guias de válvulas automotivas
Reaming is a machining process with relatively low cost and suitable when high quality holes are required. The purpose of this work is to evaluate the quality of the holes made in automotive valve guides, fabricated with sintered steel. This study was based on parameters of surface roughness, roundness and cylindricity deviations, obtained with uncoated carb
Publicado em: 2009
-
16. The UNS S32520 superduplex stainless steel processing by mechanical alloying / Processamento de aco inoxidavel superduplex uns s32520 por moagem de alta energia
The proposal of the present work is the processing of UNS S32520 commercial duplex stainless steel by high energy milling. First, using hardness by microindentation, optical and scanning electron microgaphies tests, was studied the influence of annealing between 400C and 1000C, with aim in α- phase and σ-phase precipitation. For it, was taken some
Publicado em: 2009
-
17. Study of the Machining of Intake Valve Seats of Internal Combustion Engines / Estudo da usinagem de sedes de válvulas de admissão de motores de combustão interna
As vibrações excessivas são frequentes na operação de rebaixamento de sedes de válvulas e levam o operador a reduzir a velocidade de corte ou o avanço, com prejuízo da produtividade. O objetivo deste trabalho foi estudar a usinagem das sedes de válvulas de admissão de um motor de combustão interna. As sedes são usinadas com ferramentas de PCBN a
Publicado em: 2009
-
18. Estudo da formação de interface de boreto para a deposição de diamante cvd sobre carboneto de tungstênio / Study of the formation of interface of boreto for deposition of diamond cvd on carbide of tungsten
This work developed a preparation method of an interface for adherent CVD diamond deposition on tungsten carbide sintered with cobalt (WC-Co). This method consists on reactive boron thermodiusion on WC-Co surface. This boronizing process uses a powder mixture of B_4C, KBF_4 , C e SiC, it is performed in a stainless steel crucible, at 1000°C for 5h. The bori
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 15/04/2008
-
19. Hollow cathode discharge: application of a deposition treatment in the iron sintering
The influence of a previous deposition treatment on the final amount of alloying elements (Cr and Ni) deposited and diffused into the surface of iron parts sintered in hollow cathode discharge (HCD) was studied. Cylindrical pure iron pressed samples, being a central cathode, were placed concentrically in the interior of an AISI 310 steel machine-made outer c
Journal of the Brazilian Society of Mechanical Sciences and Engineering. Publicado em: 2008-06
-
20. Sintered eutectoid P/M steel behaviour during cold upsetting
Cold upsetting experiments were carried out on sintered Fe-0.8%C steel preforms in order to evaluate the technical relationship that exist between the applied stresses against continuous deformation and densification. Powder preforms of 86% theoretical density and 0.40 of initial aspect ratio were subjected to incremental compressive loading of 0.04 MN under
Materials Research. Publicado em: 2008-03
-
21. Efeito da ferro-oxidação a vapor antes e após operação de usinagem na resistência ao desgaste de ferro sinterizado / Effect of steam treatment before and after machining operation on wear resistance of sintered steel
Neste trabalho verificou-se o efeito da ferroxidação a vapor, aplicada antes e após operações de usinagem de acabamento final, na resistência ao desgaste de um ferro sinterizado, utilizado na fabricação de bielas usadas em mancais de deslizamento de compressor hermético. Ensaios micrográficos, de dureza e microdureza, ensaios de perfil e circularid
Publicado em: 2008
-
22. Estudo da síntese e sinterização de pós compósitos do sistema Ta-Cu
Ta-Cu bulk composites combine high mechanical resistance of the Ta with high electrical and thermal conductivity of the Cu. These are important characteristics to electrical contacts, microwave absorber and heat skinks. However, the low wettability of Ta under Cu liquid and insolubility mutual these elements come hard sintering this composite. High-energy mi
Publicado em: 2008
-
23. Comparative study of porosity and pores morphology of unalloyed iron sintered in furnace and plasma reactor
Samples of unalloyed iron were sintered in the presence of an abnormal glow discharge using a confined anode-cathode configuration. The samples were placed on a holder acting as the discharge anode inside an AISI 1020 steel hollow cathode. Heating of the outer cathode was obtained by the bombardment of ions and energetic neutral particles. As a consequence o
Materials Research. Publicado em: 2007-03
-
24. Effect of rare earth oxide additions on oxidation behavior of AISI 304L stainless steel
AISI 304L stainless steel powder compacts containing 2 vol% high purity rare earth oxides were prepared by mixing the different powders in a vibratory mill followed by pressing. The compacts thus obtained were sintered in a vacuum furnace and isothermal oxidation measurements were carried out in a muffle furnace, in air, up to 200 hours at 900 °C. The oxidi
Materials Research. Publicado em: 2006-12