Menu
Search
Filters
Close
Menu

51318-10650-Effect of heat treatment on mechanical properties and corrosion resistance of Nickel Alloy UNS N0771

Picture for Effect of heat treatment on mechanical properties and corrosion resistance of Nickel Alloy UNS N0771
Available for download

An intensive testing program to study the effect of the heat treatment of the alloy USN N07718 was launched. Corrosion and environmental cracking were also tested.

Product Number: 51318-10650-SG
Author: Julia Rosenberg / Jutta Klöwer / John Groth / Christoph Bosch / Georgi Genchev
Publication Date: 2018
Industry: Science of Corrosion
$0.00
$20.00
$20.00

UNSN07718 is one of the most commonly used alloys in the oil and gas industry. The chemistry of the precipitation hardenable nickel-chromium-iron alloy is characterized by additions of niobium and molybdenum as well as certain amounts of aluminum and titanium, resulting in excellent corrosion resistance in oil and gas applications and high strength properties.

Based on the APIStandard 6ACRAthe alloy is available in two grades (min. yield strength 120 ksi and 140 ksi). Due to a strong interest in the market to have a grade with higher strength, the development of a third, 150 ksi grade was started. It is well known that the heat treatment of an alloy can have significant effects on the microstructure, mechanical properties as well as corrosion resistance. To study the effect of the heat treatment and the resultant properties of the alloy an intensive testing program of all three grades (120 ksi, 140 ksi and 150 ksi) was launched. In addition to the microstructure and mechanical properties a variety of corrosion tests were performed. The different mechanisms of environmental cracking were considered by using several test methods. Sulfide stress cracking (SSC) and galvanically induced hydrogen stress cracking (GHSC) tests were performed according to NACETM0177-2016 Method A. ETM0177-2016 Method A.

Stress corrosion cracking (SCC) resistance was investigated using C-ring tests according to NACE TM0177 Method C at Level VI/VII (NACE MR0175/ISO 15156-3, Table E.1)for 3 and 6 months. Slow strain rate (SSR) tests under cathodic polarization were performed to study the resistance to hydrogen embrittlement (HE).

In terms of resistance to corrosion and hydrogen embrittlement the 150 ksi grade of UNS N07718 was found to perform equally well or even better than the lower strength grades.

 

Key words: UNS N07718, Sulfide stress cracking (SSC), Stress corrosion cracking (SCC), Hydrogen embrittlement, 140 and 150 ksi grade.

UNSN07718 is one of the most commonly used alloys in the oil and gas industry. The chemistry of the precipitation hardenable nickel-chromium-iron alloy is characterized by additions of niobium and molybdenum as well as certain amounts of aluminum and titanium, resulting in excellent corrosion resistance in oil and gas applications and high strength properties.

Based on the APIStandard 6ACRAthe alloy is available in two grades (min. yield strength 120 ksi and 140 ksi). Due to a strong interest in the market to have a grade with higher strength, the development of a third, 150 ksi grade was started. It is well known that the heat treatment of an alloy can have significant effects on the microstructure, mechanical properties as well as corrosion resistance. To study the effect of the heat treatment and the resultant properties of the alloy an intensive testing program of all three grades (120 ksi, 140 ksi and 150 ksi) was launched. In addition to the microstructure and mechanical properties a variety of corrosion tests were performed. The different mechanisms of environmental cracking were considered by using several test methods. Sulfide stress cracking (SSC) and galvanically induced hydrogen stress cracking (GHSC) tests were performed according to NACETM0177-2016 Method A. ETM0177-2016 Method A.

Stress corrosion cracking (SCC) resistance was investigated using C-ring tests according to NACE TM0177 Method C at Level VI/VII (NACE MR0175/ISO 15156-3, Table E.1)for 3 and 6 months. Slow strain rate (SSR) tests under cathodic polarization were performed to study the resistance to hydrogen embrittlement (HE).

In terms of resistance to corrosion and hydrogen embrittlement the 150 ksi grade of UNS N07718 was found to perform equally well or even better than the lower strength grades.

 

Key words: UNS N07718, Sulfide stress cracking (SSC), Stress corrosion cracking (SCC), Hydrogen embrittlement, 140 and 150 ksi grade.

Product tags
Also Purchased
Picture for Analysis of Hydrogen Induced Cracking by in-situ HIC Observation Method
Available for download

51318-10665-Analysis of Hydrogen Induced Cracking by in-situ HIC Observation Method

Product Number: 51318-10665-SG
Author: Taishi Fujishiro / Takuya Hara
Publication Date: 2018
$20.00

New in-situ HIC measurement method to make the connection between HIC propagation behavior and microstructure. Based on an automatic ultrasonic wave inspection system and a scanning electron microscopy (SEM) observation.
Picture for Study on Ferrite Measurement Methods for Duplex Stainless Steel Welds
Available for download

51318-10634-Study on Ferrite Measurement Methods for Duplex Stainless Steel Welds

Product Number: 51318-10634-SG
Author: Nozomi Satake / Mikihiro Sakata / Tomoaki Kiso / Toshiaki Okabe /
Publication Date: 2018
$20.00

Ferrite measurements are used during welding procedures on duplex stainless steel. We studied the effects on the measured ferrite contents of (1) grid size, (2) number of fields and (3) measurement locations.

 
Picture for SSC Resistance Testing of Heavy Wall Large-Diameter Pipes using Full-Size Four-Point Bend Tests and DCB Tests
Available for download

51318-10669-SSC Resistance Testing of Heavy Wall Large-Diameter Pipes using Full-Size Four-Point Bend Tests and DCB Tests

Product Number: 51318-10669-SG
Author: Thomas Haase / Christoph Bosch / Jens Schröder / Christoph Kalwa
Publication Date: 2018
$20.00

SSC testing was performed using transverse full-size four-point bend specimens with a thickness up to 35 mm at loads up to 90 % of the actual yield strength. Finite element simulations analyzed the stress distribution under high load.
Categories
Industry
Recently viewed
Popular tags
View all

Association for Materials Protection and Performance

© AMPP All Rights Reserved.
Membership Terms of Content Use
Contact Customer Support