Bending and Welding of New High Oxidation Material - Thor™ 115

Development of materials used in the power industry for the production of USC boilers poses new challenges. The introduction of new alloying agents intended at obtaining the best possible mechanical properties, including creep resistance, affects the fabricability of new steel grades. All new materials have to undergo a lot of tests, particularly as regards bending and welding processes, with the aim of enabling the development of technologies ensuring failure-free production and assembly of boiler components. Martensitic steels containing 9% Cr, used in the production of steam superheaters shall have good creep resistance and, at the same time, low oxidation resistance at a temperature above 600°C. In turn, steels with a 12% Cr content, for example, VM12-SHC or X20CrMoV12-1 are characterized by significantly higher oxidation resistance but have lower strength at higher temperatures, which translates to their limited application in the production of modern USC and A-USC boilers.X20CrMoV12-1 was withdrawn from most of the power plants across Europe and VM12-SHC was supposed to replace it, but unfortunately, it failed in regards of creep properties. To fulfill the gap a new creep strength-enhanced ferritic steel for service in supercritical and ultra-supercritical boiler applications was developed by Tenaris and named Thor™115 (Tenaris High Oxidation Resistance). This publication covers the experience obtained during first steps of fabrication which includes cold bending and TIG welding of homogenous joints.

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Welding of Joints in New Generation Martensitic Steel THOR®115

Biuletyn Instytutu Spawalnictwa ◽

10.17729/ebis.2020.5/3 ◽

2020 ◽

pp. 21-32

Author(s):

Krzysztof Kwieciński ◽

Michał Urzynicok ◽

Antonella Ferrara ◽

Valentina Barsan

Keyword(s):

Oxidation Resistance ◽

Creep Resistance ◽

Research Work ◽

Tensile Tests ◽

Engineering Industry ◽

Martensitic Steels ◽

Higher Temperature ◽

Materials Used ◽

High Oxidation Resistance ◽

New Generation

The present development of materials used in the power engineering industry for elements of boilers characterised by supercritical parameters creates new challenges for the welding engineering sector. The implementation of new combinations of alloying agents aimed to obtain the most favourable mechanical properties, including creep resistance and oxidation resistance, does affect the weldability of steels. Martensitic steels containing 9% of Cr are characterised by high creep resistance and low oxidation resistance at temperature exceeding 600°C. In turn, steels containing 12% of Cr, i.e. VM12-SHC or X20CrMoV12-1, are characterised by significantly higher oxidation resistance but lower strength at higher temperature. In 2018, Tenaris (an Italian concern) developed new steel containing 12% of Cr and designated as THOR®115 (Tenaris High Oxidation Resistance). This article presents experience gained when making welded joints of pipes using various filler metals (W CrMo91, S Ni 6082 and EPRI P87). The research work included the performance of a series of non-destructive tests (VT, PT and RT) as well as destructive tests (tensile tests, bend tests, hardness measurements and macro and microscopic metallographic tests) aimed to confirm the high quality of the joints.

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Mechanically Activated Combustion Synthesis of Molybdenum Silicides and Borosilicides

MRS Proceedings ◽

10.1557/opl.2014.964 ◽

2014 ◽

Vol 1760 ◽

Author(s):

Mohammad S. Alam ◽

Alan A. Esparza ◽

Evgeny Shafirovich

Keyword(s):

Mechanical Properties ◽

Oxidation Resistance ◽

Power Plants ◽

Exothermic Reaction ◽

Molybdenum Disilicide ◽

Combustion Products ◽

Shs Compaction ◽

Molybdenum Silicides ◽

High Oxidation ◽

High Oxidation Resistance

ABSTRACTMolybdenum silicides and borosilicides are promising structural materials for advanced power plants. A major challenge, however, is to simultaneously achieve high oxidation resistance and acceptable mechanical properties at high temperatures. For example, molybdenum disilicide (MoSi2) has excellent oxidation resistance and poor mechanical properties, while Mo-rich silicides such as Mo5Si3 (called T1) have much better mechanical properties but poor oxidation resistance. One approach is based on the fabrication of MoSi2−T1 composites that combine high oxidation resistance of MoSi2 and good mechanical properties of T1. Another approach involves the addition of boron to Mo-rich silicides for improving their oxidation resistance through the formation of a borosilicate surface layer. In particular, Mo5SiB2 (called T2) phase and alloys based on this phase are promising materials.In the present paper, MoSi2−T1 composites and materials based on T2 phase are obtained by mechanically activated self-propagating high-temperature synthesis (MASHS). To obtain denser products, the so-called SHS compaction (quasi-isostatic pressing of hot combustion products) has been employed. Thermal analysis has shown that SHS compaction significantly improves the oxidation resistance. Self-sustained combustion of Mo/Si/B mixtures for the formation of T2 phase becomes possible if the composition is designed for adding a more exothermic reaction of MoB formation. These mixtures exhibit spin combustion. Oxidation resistance of the obtained multi-phase Mo−Si−B materials is independent on the concentration of Mo phase in the products. The “chemical oven” technique has been used to obtain a single Mo5SiB2 phase and an alloy consisting of α-Mo, Mo5SiB2, and Mo3Si phases.

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COLMONOY No. 21

Alloy Digest ◽

10.31399/asm.ad.ni0504 ◽

1996 ◽

Vol 45 (3) ◽

Keyword(s):

Cast Iron ◽

Physical Properties ◽

Oxidation Resistance ◽

Base Alloy ◽

Nickel Base Alloy ◽

Powder Metal ◽

High Oxidation ◽

High Oxidation Resistance ◽

Nickel Base

Abstract Colmonoy No. 21 is a nickel-base alloy for repairing cast iron parts. The deposit has high oxidation resistance, develops a hardness of Rockwell C 26-31, and is easily finished by filing or grinding. This datasheet provides information on composition, physical properties, and hardness. It also includes information on machining, joining, and powder metal forms. Filing Code: Ni-504. Producer or source: Wall Colmonoy Corporation.

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Ultra-high oxidation resistance of nano-structured thin films

Materials & Design ◽

10.1016/j.matdes.2021.109499 ◽

2021 ◽

Vol 201 ◽

pp. 109499

Author(s):

E. Aschauer ◽

T. Wojcik ◽

P. Polcik ◽

O. Hunold ◽

M. Arndt ◽

...

Keyword(s):

Thin Films ◽

Oxidation Resistance ◽

High Oxidation ◽

High Oxidation Resistance

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High Oxidation-resistance Coating for Steel by Using Aluminum and Titanium Powders

Tetsu-to-Hagane ◽

10.2355/tetsutohagane1955.91.1_206 ◽

2005 ◽

Vol 91 (1) ◽

pp. 206-211 ◽

Cited By ~ 5

Author(s):

Tetsuya SUZUKI ◽

Shinichi TERADA ◽

Yo TOMOTA

Keyword(s):

Oxidation Resistance ◽

High Oxidation ◽

Titanium Powders ◽

High Oxidation Resistance

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Examinations on the Oxidation Resistance of Innovative Carbon Based Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.59.92 ◽

2008 ◽

Vol 59 ◽

pp. 92-95

Author(s):

Hans Klemens Hinssen ◽

Rainer Moormann ◽

Bärbel Schlögl ◽

A. Centeno

Keyword(s):

Oxidation Resistance ◽

High Purity ◽

Temperature Treatment ◽

Oxidation Behaviour ◽

Oxidation Rates ◽

High Oxidation ◽

High Oxidation Resistance ◽

Future Work ◽

Carbon Based

An overview on parameters influencing the oxidation behaviour of carbon based materials in oxidizing gases is presented in order to support the development of advanced carbon containing materials with high oxidation resistance. Facilities for testing the oxidation behaviour, as operated in FZJ, are explained. Results of exemplary oxidation tests in air at 700°C on diverse new developed materials are presented: Ti and Zr dopings and coatings were found less efficient, whereas Si coatings/dopings significantly reduce oxidation rates. Low oxidation rates of 3D-CFCs without doping/coating, which were manufactured under temperature treatment of > 2200°C and used high purity starting materials, point out the relevance of the latter parameters. Future work on oxidation resistance of carbon based materials is shortly discussed.

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