Designing a Novel Graphitic White Iron for Metal-to-Metal Wear Systems

AbstractFrom the present study, vanadium additions up to 6.4% were added to a 14%Cr-3%C white iron, and the effect on the microstructure, hardness and abrasive wear were analysed. The experimental irons were melted in an open induction furnace and cast into sand moulds to obtain bars of 18, 25, and 37 mm thickness. The alloys were characterized by optical and electronic microscopy, and X-ray diffraction. Bulk hardness was measured in the as-cast conditions and after a destabilization heat treatment at 900°C for 45 min. Abrasive wear resistance tests were undertaken for the different irons according to the ASTM G65 standard in both as-cast and heat-treated conditions under a load of 60 N for 1500 m. The results show that, vanadium additions caused a decrease in the carbon content in the alloy and that some carbon is also consumed by forming primary vanadium carbides; thus, decreasing the eutectic M7C3 carbide volume fraction (CVF) from 30% for the base iron to 20% for the iron with 6.4%V;but overall CVF content (M7C3 + VC) is constant at 30%. Wear behaviour was better for the heat-treated alloys and mainly for the 6.4%V iron. Such a behaviour is discussed in terms of the CVF, the amount of vanadium carbides, the amount of martensite/austenite in matrix and the amount of secondary carbides precipitated during the destabilization heat treatment.

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F28-0

Alloy Digest ◽

10.31399/asm.ad.ci0064 ◽

2007 ◽

Vol 56 (9) ◽

Keyword(s):

Corrosion Resistance ◽

Physical Properties ◽

Tensile Properties ◽

Cast Alloy ◽

Heat Treating ◽

White Iron ◽

Good Corrosion Resistance

Abstract F28-0 is an abrasion-resistant cast alloy that is a martensitic white iron. The alloy possesses good corrosion resistance and is often used to handle slurries. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: CI-64. Producer or source: Kubota Metal Corporation.

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Chromium and cobalt intoxication mimicking mitochondriopathy

Neurological Research and Practice ◽

10.1186/s42466-021-00141-0 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Tim W. Rattay ◽

Torsten Kluba ◽

Ludger Schöls

Keyword(s):

Diabetes Mellitus ◽

Weight Loss ◽

Mitochondrial Dna ◽

Wear Debris ◽

Hip Prosthesis ◽

Mitochondrial Cytopathy ◽

Whole Exome ◽

Metal On Metal ◽

Metal Wear ◽

History Of

AbstractA 53-year old male with a history of progressive visual impairment, hearing loss, peripheral neuropathy, poorly controlled diabetes mellitus, cardiomyopathy, and weight loss was referred to the rare disease center due to the suspicion of mitochondrial cytopathy. In line with mitochondrial dysfunction, lactate in CSF was increased. Genetic testing by whole-exome sequencing and mitochondrial DNA did not reveal a likely cause. The case remained unsolved until he developed pain in his right hip, where he had received total hip arthroplasty 12 years earlier. An orthopedic evaluation revealed substantial shrinkage of the head of the hip prosthesis. Due to metal-on-metal wear, debris chromium and cobalt levels in serum were massively increased and significantly improved with multisystemic impairment after exchanging the defective implant.

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Effect of Minor Additives on First Stage Graphitisation in White Cast Iron

MRS Proceedings ◽

10.1557/proc-34-287 ◽

1984 ◽

Vol 34 ◽

Author(s):

P. L. Roy ◽

A. K. Chakrabart ◽

P. Banerjee

Keyword(s):

Mechanical Properties ◽

Cast Iron ◽

Sodium Chloride ◽

Yield Strength ◽

White Cast Iron ◽

Elemental Sulphur ◽

Optimum Dose ◽

White Iron ◽

Kinetics Of ◽

Strength And Ductility

ABSTRACTMinor additions (0.05-0.2 wt.%) of sodium chloride, hexachloroethane and elemental sulphur to commercial white iron melts have been found to enhance the kinetics of first stage graphitisation during subsequent annealing of white iron samples. The optimum dose of sodium chloride and hexachloroethane addition is around 0.1%. Yield strength and ductility of annealed test bars treated with NaCl or C2Cl6 compare favourably with those of untreated test bars. Sulphur treatment causes slight deterioration in mechanical properties. Fully grown nodules in both treated and untreated samples appear porous under SEM. Possible mechanisms of acceleration of graphitisation in the treated samples have been suggested.

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Suitability of a Progenitor Cell-Enriching Device for In Vitro Applications

Coatings ◽

10.3390/coatings11020146 ◽

2021 ◽

Vol 11 (2) ◽

pp. 146

Author(s):

Antonio Celentano ◽

Tami Yap ◽

Giuseppe Pantaleo ◽

Rita Paolini ◽

Michael McCullough ◽

...

Keyword(s):

Cell Viability ◽

Time Course ◽

Ex Vivo ◽

Trypan Blue Exclusion ◽

Trypan Blue Exclusion Test ◽

Initial Reduction ◽

Metal Wear ◽

Class 1 ◽

Electron Energy Loss

Rigenera® is a novel class-1 medical device that produces micro-grafts enriched of progenitors cells without ex vivo manipulation of donor tissues. The manufacturer’s protocol has been supported for a wide variety of clinical uses in the field of regenerative medicine. This study aimed to evaluate its potential use for in vitro cell models. Human primary oral fibroblasts were cultured under standard conditions and processed through Rigenera® over a time course of up to 5 min. Cell viability was assessed using a Trypan Blue exclusion test. It is possible to process fibroblasts through Rigenera® although an initial reduction of cell viability was observed. Additionally, debris was evident in the cell suspension of the processed samples. Scanning electron microscopy (SEM) microanalysis of the debris and electron energy-loss spectroscopy confirmed the presence of metal wear possibly due to the processing conditions used in this study. Interestingly, pore sizes within Rigeneracons® grids were found to range between 250–400 μm. This is the first report assessing the suitability of Rigenera® and Rigeneracons® for in vitro applications. Whilst Rigenera® workflow was found to be amenable to laboratory uses, our results strongly suggest that further research and development is necessary to support the utilization of this technology for enrichment of micro-graft derived cells and cell sorting in vitro.

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