Hervé Girard

HES-SO Valais-Wallis | HES-SO · Institut für Systemtechnik

Titanium parts are produced by the “Solvent on granule 3D-Printing” technique (SG-3DP). Angular Titanium Hydride powders are used. A special purpose table-top machine, designed and built in a previous development, is used to print green parts, which are subsequently debinded, dehydrided and sintered in a muffle furnace. Porous electrode plates are...

Nearly stoichiometric NiTi parts have been produced by selected laser melting from pre-alloyed powders. Both test specimens and complex parts have been processed. As-built parts with density higher than 99% of theoretical have been obtained. In contrast to the generally used compression testing, in this paper, the mechanical behaviour of SLM NiTi h...

The published research works on superelasticity of NiTi processed by SLM have almost only addressed mechanical behavior under compression loading. Indeed tensile loading is more challenging than compression regarding the influence of defects as cracks and pores, which can lead to premature failure even at low stress levels. Tensile behaviour should...

Aliphatic polyesters, such as polylactic acid (PLA), polyglycolic acid (PGA), and their copolymer polylactic-co-glycolic acid (PLGA) have become an established choice in the biomedical field in a wide range of applications, from nanoparticles for local drug delivery to bone fixation screws, and, hence, in a huge spectrum of uses in different medica...

Invar Fe36Ni parts are produced by the "solvent on granule" 3D-Printing technique. Both elementary and prealloyed powders are used. A special purpose tabletop machine, designed and built in a previous development, is used to print green parts, which are subsequently debinded and sintered in a muffle furnace. Prismatic specimens for thermal expansio...

Nickel-free stainless steels are of high interest for medical and dental applications, as well as consumer goods where contact with the skin is a consideration. In this paper Prof Efraín Carreño-Morelli and colleagues from the University of Applied Sciences and Arts Western Switzerland evaluate the MIM processing of the high-nitrogen content austen...

This paper presents recent developments on press and sintering of titanium from metal hydride powder. Titanium hydride offers a low cost solution compared with pure titanium powder. Different lubricants have been used for uniaxial compaction in an electric press. Dog bone specimens for tensile tests have been pressed, dehydrided and sintered. Sinte...

High-nitrogen content austenitic stainless steel parts have been processed by injection moulding of a novel feedstock composed of gas atomized P558 stainless steel powder and biopolymer-based binder. The binder formulation consists of polyhydroxyalkanoate backbone polymer produced by bacterial fermentation, filler wax and surfactant. The solids loa...

Ti-13Nb-13Zr is a low modulus near- titanium alloy developed for surgical implants. In this work, the possibility of producing Ti-13Nb-13Zr parts by metal injection moulding is evaluated. Tensile test specimens are injection moulded using a feedstock based on elemental powders, then debinded and sintered. In an attempt to further decrease the elas...

TiNi shape-memory properties are successfully used today for the fabrication of various technical devices. The limited machinability and high cost of TiNi encourage the use of near-net shape production techniques such as metal injection moulding. In this work TiNi alloys tensile test specimens are produced by metal injection moulding from pre-alloy...

Pyrovalves, i.e., valves actuated by a pyrotechnical device, are very often used in space propulsion systems for their fast response, high reliability, low mass and low cost. However, they are hazardous and single use items. Their operation induces shocks and can generate contaminants. If a slower actuation is required or possible, shape memory-bas...

Ti–Nb alloys are attractive as biomaterials because of their excellent combination of low elastic modulus, high strength, corrosion resistance and enhanced biocompatibility. The effect of a post-sintering quenching treatment on the microstructure and mechanical properties of powder injection moulded Ti–17Nb has been investigated. Tensile test speci...

Recent developments are presented on powder injection moulding of titanium from metal hydride powders and binders composed of polyethylene, paraffin wax and stearic acid. The feasibility of using this route to process fit for purpose, complex parts is assessed. Titanium hydride offers a low cost solution compared with pure titanium powders. Feedsto...

Powder Injection Molding (PIM) gives the possibility to produce, at an industrial rate, ceramic parts with fine details. It is thus a possible approach to reduce the fabrication costs of Solid Oxide Fuel Cells (SOFCs). This work presents fabrication and electrochemical characterization results of injection-molded structured anode-supported SOFCs.Pl...

Powder injection moulding is an enabling technology for the production of soft ferromagnetic components, which bring solutions and open the way for new applications. In this work, square toroid parts have been injection moulded for three typical soft magnetic alloy compositions. Fe2.7Si, Fe50Ni and Fe50Co feedstocks were produced by mixing elementa...

Titanium thin sheets have been fabricated by tape casting using slurries based on titanium hydride powder. Titanium hydride is attractive because of its reduced cost with respect to pure titanium. Sheets of various thicknesses were tape cast, debinded, dehydrided and sintered. Porous sheets with even surfaces were obtained. Scanning electron micros...

INTRODUCTION: The fabrication of titanium-based implants and medical devices usually needs several complex steps 1. Net-shape processing by powder injection moulding (PIM 2) of titanium hydride powders, which are cheaper and less reactive than titanium powders, can be the solution for breaking the cost barrier 3 .

Solid Oxide Fuel Cells (SOFC) are a promising technology for high efficiency energy conversion. Powder injection moulding (PIM) is a possible approach to reduce the fabrication costs of SOFC. Components in the form of bars and disks with an intricate pattern of small details have been produced by injection moulding of nickel oxide (NiO) and yttria-...

Titanium parts have been processed from feedstocks composed of titanium hydride powders, low density polyethylene, paraffin wax and stearic acid. A two-step debinding process has been used, which consists of solvent debinding in heptane at 50°C followed by thermal debinding at 500°C. Sintering was performed at 1200°C. Both thermal debinding and sin...

Titanium parts have been processed from feedstocks composed of titanium hydride powders, low density polyethylene, paraffin wax and stearic acid. A two-step debinding process has been used, which consists of solvent debinding in heptane at 50°C followed by thermal debinding at 500°C. Sintering was performed at 1200°C. Both thermal debinding and sin...

The fabrication of Cu-Al-Ni-Mn alloys by tape casting followed by hot-compaction has been investigated. A slurry composed of a mixture of metallic powder, solid lubricant, binder, plasticizer and solvents has been used. Dense and chemically homogeneous Cu-Al-Ni-Mn shape-memory alloys have been obtained. The microstructure of the sintered compacts h...