Tribomechanical Behaviour of TiAlN and CrAlN Coatings Deposited onto AISI H11 with Different Pre-Treatments

In the metalworking industry, different processes and applications require the utilisation of custom designed tools. The selection of the appropriated substrate material and its pre-treatment as well as the protective coating are of great importance in the performance and life time of forming tools, dies, punches and coated parts in general. TiAlN and CrAlN coatings have been deposited onto the hot work tool steel AISI H11 by means of Direct Current Magnetron Sputtering. Prior to the deposition, the steel substrate was modified by the implementation of three different pre-treatments: nitriding of the annealed substrate [Nitr.], heat treatment of the steel (quenching and double tempering) [HT] and nitridation subsequent to a heat treatment of the substrate [HT + Nitr.]. The purpose of this research is to obtain valuable information on the microstructural properties and tribomechanical behaviour of two of the most promising ternary transition metal nitride coatings, TiAlN and CrAlN, when deposited on the AISI H11 steel with different initial properties. The different pre-treatments performed to the steel prior to the deposition favour the tailoring during the design and construction of tools for specific applications. The microstructure, the adhesion and the wear resistance of TiAlN coatings were highly influenced by the substrate preparation. Contrarily, CrAlN results were more independent of the substrate preparation and no high influences were found. For instance, the adhesion of the TiAlN coating varied from 17 to 43 N for the coating deposited onto the HT + Nitr. substrate and the HT substrate respectively, while the lowest and highest adhesion of the CrAlN coating varied between 42 and 53 N for the HT and the HT + Nitr. respectively. Likewise, the wear coefficient of the CrAlN were ten times smaller than those found for the TiAlN coatings, presumably due to the presence of hex-AlN phases and the small differences on the Young´s Modulus of the substrate and the CrAlN coatings.

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Effects of heat treatment on microbial communities of granular sludge for biological hydrogen production

Water Science & Technology ◽

10.2166/wst.2012.336 ◽

2012 ◽

Vol 66 (7) ◽

pp. 1483-1490 ◽

Cited By ~ 22

Author(s):

Luca Alibardi ◽

Lorenzo Favaro ◽

Maria Cristina Lavagnolo ◽

Marina Basaglia ◽

Sergio Casella

Keyword(s):

Heat Treatment ◽

Hydrogen Production ◽

Microbial Communities ◽

Granular Sludge ◽

Dark Fermentation ◽

Anaerobic Granular Sludge ◽

Batch Test ◽

Ph Values ◽

Pre Treatment ◽

Selection Of

Dark fermentation shares many features with anaerobic digestion with the exception that to maximize hydrogen production, methanogens and hydrogen-consuming bacteria should be inhibited. Heat treatment is widely applied as an inoculum pre-treatment due to its effectiveness in inhibiting methanogenic microflora but it may not exclusively select for hydrogen-producing bacteria. This work evaluated the effects of heat treatment on microbial viability and structure of anaerobic granular sludge. Heat treatment was carried out on granular sludge at 100 °C with four residence times (0.5, 1, 2 and 4 h). Hydrogen production of treated sludges was studied from glucose by means of batch test at different pH values. Results indicated that each heat treatment strongly influenced the granular sludge resulting in microbial communities having different hydrogen productions. The highest hydrogen yields (2.14 moles of hydrogen per mole of glucose) were obtained at pH 5.5 using the sludge treated for 4 h characterized by the lowest CFU concentration (2.3 × 103CFU/g sludge). This study demonstrated that heat treatment should be carefully defined according to the structure of the sludge microbial community, allowing the selection of highly efficient hydrogen-producing microbes.

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1671: Association of Race, Cancer Severity, Pre-Treatment Quality of Life, and Patient Optimism/Pessimism with Patient Selection of Primary Prostate Cancer Treatment

The Journal of Urology ◽

10.1016/s0022-5347(18)35793-8 ◽

2005 ◽

Vol 173 (4S) ◽

pp. 453-453

Author(s):

Martin G. Sanda ◽

Rodney L. Dunn ◽

Christopher S. Saigal ◽

Eric A. Klein ◽

Louis L. Pisters ◽

...

Keyword(s):

Quality Of Life ◽

Prostate Cancer ◽

Cancer Treatment ◽

Patient Selection ◽

Treatment Quality ◽

Prostate Cancer Treatment ◽

Primary Prostate Cancer ◽

Pre Treatment ◽

Selection Of

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BÖHLER W403 VMR

Alloy Digest ◽

10.31399/asm.ad.ts0721 ◽

2013 ◽

Vol 62 (9) ◽

Keyword(s):

Heat Treatment ◽

Chemical Composition ◽

Physical Properties ◽

Tool Steel ◽

Raw Materials ◽

Heat Treating ◽

Diffusion Annealing ◽

Selection Of

Abstract Böhler (or Boehler) W403 VMR is a tool steel with outstanding properties, based not only on a modified chemical composition, but on the selection of highly clean raw materials for melting, remelting under vacuum (VMF), optimized diffusion annealing, and a special heat treatment. This datasheet provides information on composition, physical properties, and elasticity. It also includes information on forming and heat treating. Filing Code: TS-721. Producer or source: Böhler Edelstahl GmbH.

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Volume reduction of produced water generated from natural gas production process using membrane technology

Water Science & Technology ◽

10.2166/wst.2000.0622 ◽

2000 ◽

Vol 41 (10-11) ◽

pp. 117-123 ◽

Cited By ~ 10

Author(s):

C. Visvanathan ◽

P. Svenstrup ◽

P. Ariyamethee

Keyword(s):

Natural Gas ◽

Produced Water ◽

Hollow Fibre ◽

Gas Production ◽

Oil And Grease ◽

Natural Gas Production ◽

Pre Treatment ◽

Selection Of ◽

Spiral Wound

This paper presents a case study of a natural gas production site covering various technical issues related to selection of an appropriate Reverse Osmosis (RO) system. The long-term field experience indicates the necessity of the selection of appropriate pretreatment systems for fouling-free RO operational conditions. The produced water has a variety of impurities such as oil and grease, process chemicals used for corrosion and scaling control, and dehydration of natural gas, etc. This situation leads to a complicated and extremely difficult task for a membrane specialist to design RO systems, especially the pre-treatment section. Here as part of the pretreatment selection, two types of UF membrane modules viz. spiral wound and hollow fibre, with MWCO of 8000 and 50,000 Dalton respectively, were tested in parallel with NF membranes of the spiral wound type with MWCO 200 Dalton. The UF permeate is used as feed for RO compatibility testing. Both configurations of UF failed to be compatible, due to irreversible fouling of the RO membrane. The NF membrane, however, showed interesting results, due to membrane stability in terms of cleaning and fouling. The NF plant with 50% capacity gave a recovery of 75% and the RO plant gave a recovery of 60% versus the expected 92–95%. The long-term tests have indicated that the reminder of the membranes could be installed to achieve full capacity of the plant. This study also demonstrates the importance of selection of proper pre-treatment set-up for the RO system design.

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Preparation of β-PbO2 and β-PbO2-MnO2 Coating on Stainless Steel Substrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.490-495.3486 ◽

2012 ◽

Vol 490-495 ◽

pp. 3486-3490

Author(s):

Qiang Yu ◽

Zhen Chen ◽

Zhong Cheng Guo

Keyword(s):

Stainless Steel ◽

Mass Fraction ◽

Stainless Steel Substrate ◽

Steel Substrate ◽

Substrate Material ◽

X Ray Diffraction ◽

X Ray ◽

New Type ◽

Plating Solution ◽

Element Mass Fraction

In order to prepare a new type of anode material, stainless steel was selected as substrate material. The β-PbO2 coating on stainless steel substrate was prepared under the appropriate plating solution, and the PbO2-MnO2 coating was prepared with thermal decomposition. The crystal structure was determined by X-ray diffraction; Surface morphology was test by Scanning Electron Microscopy; the energy spectrum was used to determine element mass-fraction and the ratio of atomic number of the coatings.

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Fabrication and characterization of composite MoS2-TiO2 coating material

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/09544062211015789 ◽

2021 ◽

pp. 095440622110157

Author(s):

Avinash V Borgaonkar ◽

Ismail Syed ◽

Shirish H Sonawane

Keyword(s):

Bond Strength ◽

Treatment Method ◽

Optical Microscope ◽

Scratch Resistance ◽

Substrate Material ◽

Coating Film ◽

Tribological Behaviour ◽

Molybdenum Disulphide ◽

Before And After ◽

Pre Treatment

Molybdenum disulphide (MoS2) is a popularly used solid lubricant in various applications due to its superior tribological behaviour. However, it possesses poor wear resistance which requires further improvement. In the present study efforts have been made to enhance the tribological properties of pure MoS2 coating film by doping TiO2 nanoparticles as a reinforcement material. The Manganese phosphating is selected as a pre-treatment method to improve the bond strength between coating and substrate. The coating is bonded with the substrate material employing sodium silicate as a binder. The effects of wt. % of TiO2 onto the mechanical properties of composite MoS2-TiO2 coating such as hardness and bond strength have been studied. In addition coating microstructure before and after experimental test was studied using optical microscope and scanning electron microscope. It was also found that with increase in wt. % addition of TiO2 upto 15% into MoS2 base matrix, the hardness of coating increases proportionally. Beyond 15 wt. % addition of TiO2, the coating becomes brittle in nature. This leads to reduction in the scratch resistance.

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Some Regularities of Life Time and Damage for the New Structural Material MoNiCa during Sliding Friction and Mechano-Sliding Fatigue

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.320.90 ◽

2021 ◽

Vol 320 ◽

pp. 90-96

Author(s):

Aliaksandr Bahdanovich ◽

Sergei Sherbakov ◽

Ivan Lis ◽

Regita Bendikiene ◽

Ramūnas Česnavičius ◽

...

Keyword(s):

Heat Treatment ◽

Structural Material ◽

Mechanical System ◽

Sliding Friction ◽

Limit State ◽

High Strength ◽

Life Time ◽

Average Wear ◽

The Republic ◽

Number Of Cycles

The results of an experimental study of damage for the structural material MoNiCa (it is high-strength cast iron VCHTG – patent of the Republic of Belarus № 15617) on sliding friction and mechano-sliding fatigue are analyzed in the report. Tests of the mechanical system shaft (a sample with a working part diameter of 10 mm made of 0.45 % carbon steel) - an insert (a prismatic counter sample with a cross section of 10 ´ 10 mm made of MoNiCa) were carried out. The kinetics of the change in average wear at 8 local points along the perimeter of the dangerous area of the sample is given for contact loads FN from 20 to 92 N of the mechanical system under study with MoNiCa inserts without heat treatment and with heat treatment. The test results of the system under study are also presented in the form of sliding friction and mechano-sliding fatigue curves in coordinates of the contact load FN – the number of cycles N until the limit state.

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Influence of Laser Heat Treatment on Fracture Strength of Ceramic Thin Film

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.566.145 ◽

2012 ◽

Vol 566 ◽

pp. 145-149

Author(s):

Hirotaka Tanabe ◽

Keiji Ogawa ◽

Yui Izumi ◽

Tohru Takamatsu ◽

Heisaburo Nakagawa ◽

...

Keyword(s):

Thin Films ◽

Heat Treatment ◽

Fracture Strength ◽

Strength Loss ◽

Substrate Material ◽

Laser Quenching ◽

Ceramic Thin Films ◽

Film Hardness ◽

Induced Changes ◽

Substrate Hardness

In our previous study, it has been shown that improvement of the adhesive strength and substrate hardness of ceramic coated steels without compromising the film hardness can be achieved by applying laser quenching. In the present research, in order to demonstrate further development of this method, the fracture strength of laser-irradiated ceramic thin films (CrAlN, TiAlN and CrN) was investigated by sphere indentation testing. To prevent heat-induced changes in the substrate hardness, a cemented carbide WC-Co rather than steel was used as substrate material. While the fracture strength of each film decreased significantly through furnace heat treatment, it remained almost unchanged in case of the laser irradiated films. Laser quenching has been shown to effectively reduce the fracture strength loss of the ceramic thin films in coated steels.

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Enhancement of Life Time of the Dimensionally Stable Anode for Copper Electroplating Applications

Archives of Metallurgy and Materials ◽

10.1515/amm-2017-0145 ◽

2017 ◽

Vol 62 (2) ◽

pp. 1019-1022 ◽

Cited By ~ 1

Author(s):

Seong Ho Son ◽

Sung Cheol Park ◽

Man Seung Lee

Keyword(s):

Metal Oxides ◽

Noble Metal ◽

Titanium Substrate ◽

Life Time ◽

Oxide Thickness ◽

Surface Pretreatment ◽

Copper Electroplating ◽

Noble Metal Oxides ◽

Pre Treatment ◽

Electroplating Process

Abstract In order to enhance the long-term stability of DSA for copper electroplating process, in the present study, noble metal oxides with excellent electrochemical properties was used and optimum condition was determined the ratio of noble metal oxides, surface pre-treatment of titanium substrate and heat treatment. The effect of the surface pretreatment of titanium substrate and ratio of noble metal oxides were estimated by accelerated test at the highly current density conditions. The lifetime of DSA increase six-fold higher as the oxide thickness of Ta 7 : Ir 3 composition ratio. Under the optimal condition, surface pretreatment led to dramatic increase in the lifetime of DSA.

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