Diffusible hydrogen

Specimens of various sizes are used to determine hydrogen content in deposited metals in such standards as ISO 3690, AWS A 4.3, and GOST 23338 while measuring methods are the same. It causes problems in comparison of experimental results and brings up the following question: what kind of specimen size is optimal to determine hydrogen content? An optimal specimen size was estimated using a calculation method. Experimental and calculation results obtained by using specimens with estimated dimensions were compared to the results obtained by using the specimen with dimensions of 100*25*8 mm to determine hydrogen content in a deposited metal.

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Coating of Electrode by Myristic Acid via Microwave Reaction

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.306-307.544 ◽

2011 ◽

Vol 306-307 ◽

pp. 544-547

Author(s):

Wen Jun Chen ◽

Chi Bin Gui ◽

Ji Sun

Keyword(s):

Petroleum Ether ◽

Electrode Surface ◽

Myristic Acid ◽

Microwave Oven ◽

Light Petroleum ◽

Absorption Property ◽

Diffusible Hydrogen ◽

Deposited Metal ◽

Microwave Reaction ◽

Ft Ir

Electrodes can absorb moisture easily so that the diffusible hydrogen is quite high in the weld bead. Fe3O4 powder is used to promote the reaction of myristic acid and the electrode surface, and reduce the diffusible hydrogen, because of its excellent microwave absorption property. Electrodes are immersed to the light petroleum solution which contains myristic and Fe3O4 particles, then they are put into the microwave oven and become water-resistant . The results of FT-IR and SEM microscope indicate that Fe3O4 powder absorb microwave and melt myristic acid to form the water-resistant film. The best ratio of myristic acid in the petroleum ether is 18% and the diffusible hydrogen of the deposited metal of microwave treated electrode decreased to 83% of the untreated electrode.

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Research Regarding Wear Protection in Sever Exploitation Condition of Crusher Jaws

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1128.390 ◽

2015 ◽

Vol 1128 ◽

pp. 390-393

Author(s):

Daniel Tihanov Tanasache ◽

Emilia Binchiciu ◽

Carmen Florea ◽

Victor Geanta ◽

Horia Binchiciu

Keyword(s):

High Pressure ◽

Active Surface ◽

Protection System ◽

Innovative Technology ◽

Diffusible Hydrogen ◽

Wear Area ◽

Base Materials ◽

Wear Protection ◽

Self Protection ◽

Fall Deposits

The paper presents a new innovative technology that is experimented to protect from wear crusher jaws that grind basalt aggregates. These are subjected, in exploitation, at the active surface level, to complex requests of wear at abrasion under high pressure combined with fatigue at high efforts. Actual developed stage in casted form from hardened steels present the disadvantage of being sensitive to excavation, pitting type, wear, in hard areas or in those with segregation at the crystalline grain limit. Fighting the above mentioned phenomena’s if accomplished by loading through welding on the jaws active surfaces layers with proper proprieties to obtain intelligent self-protection to wear systems. The thickness of the deposits is determined experimental based on minimizing the tensions on the base metal. The position and geometry of the wear self-protection system were established on data collected from crusher jaws used in exploitation, in Bata quarry, Romania. The morphology of the wear self-protection system layers is developed depending on the type of wear it will encounter during exploitation. Thus in the central impact and wear area, under abrasion and high pressure, depositing the self-protection at wear system consists of alternative rows of tough, hardened, with small grain size materials; in the side areas, subjected to the constant grinded material fall, deposits developed with tough materials. To assure the manufacturing process for the new products, at Sudotim AS Timișoara, we experimentally adapted rods SUDODUR CWTV and SUDINOX CN according to quality-price conditioned imposed as well as its lifespan in exploitation. Requests followed optimizing the product based on minimum price, minimum alloying level and low level of diffusible hydrogen and high purity of base materials.

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Fatigue Crack Growth Rate and Fracture Toughness of API5L X65 in Sweet Environments

Volume 3: Materials Technology; Ocean Space Utilization ◽

10.1115/omae2013-10216 ◽

2013 ◽

Cited By ~ 1

Author(s):

Michael A. Tognarelli ◽

Ramgopal Thodla ◽

Steven Shademan

Keyword(s):

Fracture Toughness ◽

Growth Rate ◽

Fatigue Crack ◽

Crack Growth Rate ◽

Fatigue Crack Growth ◽

Crack Growth ◽

Fatigue Crack Growth Rate ◽

Environmental Conditions ◽

Initiation Toughness ◽

Diffusible Hydrogen

Corrosion fatigue and fracture toughness in sour environments of APIX65 5L have typically been studied in relatively severe environments like NACE A and NACE B solutions. There are very limited data in sweet and mildly sour environments that are of interest in various applications. This paper presents fatigue crack growth frequency scans in a range of sweet and mildly sour environments as well as on different microstructures: Parent Pipe, Heat Affected Zone (HAZ) and Weld Center Line (WCL). The fatigue crack growth rate (FCGR) increased with decreasing frequency and reached a plateau value at low frequencies. FCGR in the sweet environments that were investigated did exhibit a frequency dependence (increasing with decreasing frequency) and had plateau FCGR in the range of 10–20× the in-air values. In the mildly sour environments that were investigated, FCGR was found to be about 25 to 30× higher than the in-air values. By comparison, in NACE A environments the FCGR is typically about 50× higher than the in-air values. The FCGRs of parent pipe and HAZ were found to be similar over a range of environments, whereas the WCL FCGR data were consistently lower by about a factor of 2×. The lower FCGR of the WCL is likely due to the lower concentration of diffusible hydrogen in the weld. FCGRs as a function of ΔK (stress integrity factor range) were measured on parent pipe at the plateau frequency. The measured Paris law curves were consistent with the frequency scan data. Rising displacement fracture toughness tests were performed in a range of sweet and sour environments to determine the R-curve behavior. Tests were performed in-situ at a slow K-rate of 0.05Nmm−3/2/s over a range of environmental conditions on parent pipe. The initiation toughness and the slope of the R-curve decreased sharply in the sour environments. The initiation toughness and slopes were largely independent of the notch location as well as environmental conditions. Typical values of initiation toughness were in the range of 90–110N/mm.

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