DELORO STELLITE 25

Deloro Stellite 25 is a cobalt-chromium-tungsten-nickel alloy. This tungsten strengthened cobalt-chromium alloy is the cast version of the wrought cobalt-base alloy L605. Deloro Stellite 25 is resistant to wear, galling, and corrosion and retains this resistance at high temperatures. Its exceptional wear resistance is due mainly to the unique inherent characteristics of the hard carbide phase dispersed in a CoCr alloy matrix. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as machining. Filing Code: Co-142. Producer or source: Deloro Wear Solutions GmbH.

EFFECT OF HOT CORROSION AND OXIDATION ON COBALT - BASE SUPERALLOYS COATED BY ALUMINUM WITH PRESENCE OF THERMAL BARRIER ZRO2 AND MIXTURE OF (NACL) AND (NA2SO4) STEAMSALTSAT HIGH TEMPERATURES

The aim of the study was to investigate the Mechanisms properties of thermal barrier coatings (TBCs) to enhance of performance evaluation characteristics and develop TBCs.Cobalt –base superalloy has been used as a substrate and zirconium stabilized Aluminum as ceramic topcoat , in addition the study include degradation behavior of system during thermal cycling (3hr per cycle in furnace) the failure of the aluminized was due to thermally grown oxide (TGO) interface. The fractures propagatethrough the interface and produce a deformation of the bond coating . the effect of cycle will result a spallation failure of the TBCsand this is also corresponding to a slightdegradation .The steam of salt (Nacl)and(Na2So4) mixture will affecton the coating lifetimes .The high temperature have a strong effect thermally grown oxide (TGO) which consistent with a first order growth of scale failer variation.

Effect of Heat Treatment on the Microstructure and Mechanical Properties of a Co-Based Superalloy Strip

In this paper, the effect of heat treatment on the microstructure and mechanical properties of a deformed Co-Cr-Ni-W superalloy strip was investigated. The cold-rolled superalloy was annealed at different temperatures 500°C~1240°C for 10min. It was found that hardness increased in the range temperature 500°C~800°C, the annealing had aging strengthening effect, this was due to the fcc~hcp transformation. As the annealing temperature is higher than 800°C, the hardness decreased with the increase of the annealing temperature. There were four inflection points in the influence of annealing temperature on the hardness of the alloy, which were about 800°C,900°C,1050°Cand 1150°C. From 800°C to 900°C, the hardness of the alloy decreased rapidly, recovery and recrystallization was initial. From 900°C to 1050°C, the hardness of the alloy decreased slower, recrystallization was finished and grain growth slowly. The temperature reaches 1050°C to 1150°C, the hardness curve decreased rapidly, carbides dissolution and grain growth was considerable. Above 1150°C, the hardness tended to be stable, the grain growth of the alloy was obvious, and more annealing twins were also formed. As the annealing temperature increased, the tensile strength decreased and the elongation increased. Keywords Cobalt-base superalloy; Heat treatment; Microstructure; Mechanical Properties Yong-Ji Niu,Yue Zhang University of Science and Technology Beijing,Beijing 100083,china; e-mail: [email protected] Yong-Ji Niu, Zhi-Wei Zhang, Ning An, Yang Gao Beijing Beiye Functional Materials Corproration, Beijing 100192, China

Osseointegration Improvement of Co-Cr-Mo Alloy Produced by Additive Manufacturing

Cobalt-base alloys (Co-Cr-Mo) are widely employed in dentistry and orthopedic implants due to their biocompatibility, high mechanical strength and wear resistance. The osseointegration of implants can be improved by surface modification techniques. However, complex geometries obtained by additive manufacturing (AM) limits the efficiency of mechanical-based surface modification techniques. Therefore, plasma immersion ion implantation (PIII) is the best alternative, creating nanotopography even in complex structures. In the present study, we report the osseointegration results in three conditions of the additively manufactured Co-Cr-Mo alloy: (i) as-built, (ii) after PIII, and (iii) coated with titanium (Ti) followed by PIII. The metallic samples were designed with a solid half and a porous half to observe the bone ingrowth in different surfaces. Our results revealed that all conditions presented cortical bone formation. The titanium-coated sample exhibited the best biomechanical results, which was attributed to the higher bone ingrowth percentage with almost all medullary canals filled with neoformed bone and the pores of the implant filled and surrounded by bone ingrowth. It was concluded that the metal alloys produced for AM are biocompatible and stimulate bone neoformation, especially when the Co-28Cr-6Mo alloy with a Ti-coated surface, nanostructured and anodized by PIII is used, whose technology has been shown to increase the osseointegration capacity of this implant.

Tribomaterials

Tribomaterials: Properties and Selection for Friction, Wear, and Erosion Applications provides practical information on the tribological behaviors of engineering materials, how they are measured, and how to account for them in order to optimize product lifetime and performance. The first few chapters describe the mechanisms and manifestations of various types of friction, erosion, and wear and how to assess their impact on design and equipment operation using proven tribotesting methods. The chapters that follow cover the tribological properties and characteristics of important engineering materials, including carbon and low-alloy steels, tool steels, stainless steels, nickel- and cobalt-base alloys, copper alloys, and cast iron as well as ceramics, cermets, cemented carbides, polymers, and polymer composites. The book also includes chapters on treatments and coatings, lubrication, and the selection and screening of materials for tribosystems, including medical applications. Each chapter ends with a review of terms, takeaway concepts, essential questions, and related reading. For information on the print version, ISBN: 978-1-62708-321-8, follow this link.

Tribological Properties of Stainless Steel and Other Corrosion-Resisting Metals

This chapter covers the tribological properties of stainless steel and other corrosion-resistant alloys. It describes the metallurgy and microstructure of the basic types of stainless steel and their suitability for friction and wear applications and in environments where they are subjected to liquid, droplet, and solid particle erosion. It also discusses the tribology of nickel- and cobalt-base alloys as well as titanium, zinc, tin, aluminum, magnesium, beryllium, graphite, and different types of wood.