Abstract The 316L stainless steel (316L SS) is one of the most used metallic materials for implants, due to its high mechanical properties and low cost. However, it is bioinert. One possibility to improve its biocompatibility is the production of a composite with b-tricalcium phosphate (β-TCP) addition. This study investigated the mechanical behavior of 316L SS/β-TCP composites through powder metallurgy. For this, used were 3 compositions, with 0 %, 5 % and 20 % of β-TCP. The compositions with 5% and 20% were milled during 10 hours with a mass/sphere ratio of 1:10 and 350 rpm. All compositions were uniaxially pressed with 619 MPa and sintered during 1 hour at 1100ºC. The microstructural and mechanical evaluations were performed through scanning electron microscopy, density and compressive strength. The results indicated that, by increasing the percentage of β-TCP in the compositions, the mechanical resistance decreases, as a consequence of its low load support.

Abstract This study aims to analyze the efficiency of niobium and vanadium carbides in the high energy mechanical milling of aluminum bronze alloy. Two series of experiments were made following the same steps for both niobium carbide (NbC) and vanadium carbide (VC) additions: 30 g of chips were weighed and placed in a stainless steel jar with 3 % of carbide and 1 % of stearic acid for a mass/sphere relationship of 1:10. The milling was realized using a planetary ball mill for 10, 30 and 50 hours in an inert argon atmosphere at 300 rpm. Results shown in laser diffraction indicate a great reduction in the particle sizes of powders when VC is used. For 30 hours milling, D50 values ranged from 1580 µm with NbC to 182.3 µm with VC addition. The D50 values ranged from 251.5 µm with NbC to 52.26 µm with VC addition, for 50 hours milling. The scanning electron microscopy showed that in 10 hours of milling, the energy was not sufficient to achieve the shear of chips in both cases. For 30 hours, it's possible to observe particles with sizes between 100 µm and 800 µm with NbC addition while for the same milling time, with VC it's possible to see particles with different sizes, but with many shapes of fine particulates. For 50 hours milling, particles achieved the smaller sizes between 50 and 200 µm with NbC and ranging from 5 until 50 µm with VC addition.

In this study, the high energy mechanical milling was utilized to the production of duplex stainless steel powders from the recycling chips with and without the addition niobium carbide. The effect of milling time and addition carbide on the morphology, particle size and magnetic properties of the powders was investigated. The utilization of the powder metallurgy constitute an important alternative for the reuse of waste in the industrial sector. The milling was realized using a planetary ball mill for 20 hours at a milling speed of 350 rpm and ball-to-powder weight ratio of 15:1were used, and the (0% and 3 wt. %) niobium carbide (NbC) addition. Scanning electron microscopy and particle distribution analysis were used for characterization of morphology and measure of particle size. Also, to analyze the transformations of phases were investigated using the magnetic characterization and x-ray diffraction. The results indicated that the addition of niobium carbide results in the reduction of the particle size of steel of the order of 20%, besides the reduces the transformation of austenite into strain induced martensitic phase.