Test methods carbon steel

This study was in real time measured that the reflective echo height of the bonding interface in the solid phase diffused bonding process of carbon steel and titanium using ultrasonic testing method. As a result, the following were made discernment. 

AU other carbon steel, low-intermediate, and high-aUoy steels, ferritic steels Base metal Deposited weld metal and heat-affected zone (See Note 1) 2. Except when conchtions conform to Note 2, the material shall be heat-treated to control its microstructure by a method appropriate to the material as outlined in the specification applicable to the product form and then impact-tested. (See Note 1.) Deposited weld metal and heat-affected zone shall be impact-tested. 

Cihal and Prazak determined the resistance of 18/8 stainless steel to this type of corrosion. They claimed that the technique could be used on steels which are difficult to test by other methods, including steels of low carbon content, and steels in which stabilising elements are present. By means of potentiostatic curves and light etching at constant potential they confirmed that the extent of intergranular corrosion depended upon the amount of precipitated chromium carbide. 

The ASTM Corrosion Test procedure by Total Immersion Method requires that all specimens in a test series should have the same dimensions when comparisons are to be made. In these experiments, carbon steel was used representing the pipeline material. The coupons were cleaned, polished and weighed. Coal-water slurry, 10 to 40 weight percent, was used in the corrosion tests. For the coal-water slurry the intitial pH of the medium varied from 2.3 to 2.6 and the test series containing the nutrient media, the microorganisms and the inhibitors the pH varied from 2 to 2.5. Specimens were immersed in the reaction vessel maintained at a constant temperature of 86°F for 72 hours or the specified time. The coupons were removed, washed with deionized water, dried and weighed. The loss in weight of the specimen, before and after the test was attributed to corrosion. 

Table 9.1 summarizes environmental alloy combinations that have been shown to produce see. The test temperature accelerates the See for most of the systems listed in Table 9.1. Electrochemical methods and stress corrosion tests should be performed to evaluate possible corrosion environments for a given alloy. More information on these and additional systems may be found in the ASM Metals Handbook [30]. Other significant alloys include nickel alloys [31], austenitic stainless steel [30], carbon steels [32], copper alloys [33], ferritic, martensitic, duplex [31,32], titanium alloys [33], and aluminum alloys [34].

An alternative method of this test has been developed. The punch travel between the initial contact with the specimen and the onset of a drop in the punch load, which is associated with the formation of a visible crack, is determined and used instead of the ratio of diameters. This value, termed the formability index, correlates with the uniform elongation and, thus, with the n value for low-carbon steels. 

Properties ASTM Test Method 40% Glass- and Mineral-reinforced 40-45% Mineral-filled 30% Graphite or PAN Carbon Eiber 40% Aluminum Flake 5% Stainless Steel, Long Eiber 6% Stainless Steel, Long Eiber... 

In most instances, corrosion test methods for plain carbon steels, high-strength low-alloy steels, and alloy steels do not differ greatly. Therefore, these steels are grouped together for the purposes of this chapter. (Alloy steels here refers to heat treatable constructional and automotive steels, and does not include the stainless steels or other high alloys.) There are some differences in the corrosion test methods used for different mill products of this group of steels, and these will be discussed. The steels covered in this chapter are defined below. 

Electrochemical tmodic polarization tests (ASTM G 5 and G 61 ) are useful corrosion test methods for alloy and process development work on P/M materials. Reference 23 describes the application of potentiostatic anodic polarization to steam-treated P/M carbon steel in neutral salt and acidic environments. References 13 and 19 describe the application of potentiodynamic polarization to sintered austenitic stainless steels. These test methods are very effective in revealing metallurgical weaknesses of sintered stainless steels. Sintered stainless steels, due to their large surface areas, exhibit large corrosion currents, compared to the wrought stainless steels, and frequently the current rises with increcising potential. Furthermore, sintered stainless steels do not always exhibit a pronoimced transition ftom... 

LPR testing is typically done in accordance with ASTM Standard G 96. Yeske [154] measured the corrosion rates of carbon steels in alkaline sulfide environments using the LPR technique and described the use of the silver/silver sulfide reference electrode. These techniques were develop>ed further by Crowe and Yeske [755] and used with real mill liquors for on-line monitoring of corrosion rates. The corrosion rates were found to be related to liquor composition with a strong flow effect. Crowe [156] also used LPR testing for on-line corrosion monitoring in white liquor clarifiers. Leinonen et al. [757] used the LPR method to monitor corrosion in a batch digester. 

The mechanistic differences between SSC and SCC (anodic type) have a significant influence on the test methods used. Stated simply, the critical vciriable in SSC of carbon and low-alloy steels is the stress (strain) required to initiate and sustain cracking in an arbitrarily selected severe environment. In SCC, the critical variables are the electrochemical polarization characteristics of the metal/environ-ment system that control the anodic processes involved in crack initiation and growth. Therefore, alloy SCC susceptibility comparisons are done by determining the critical environmental factors (e.g., temperature, H2S partial pressure, chloride concentration) required to cause failure of a severely stressed specimen. 

Some crude oils contain significant concentrations of organic acids, mainly napthenic acids, which are corrosive to carbon steel at temperatures above about 400 F (200°C), and may require the use of molybdeniun-containing austenitic stainless steels (i.e., AISI316 and 317). Determination of when to use alloys is done by analysis of the crude oil for acid content using ASTM D 974, Test Method for Acid and... 

Base Number by Color-Indicator Titration ASTM D 664, Test Method for Acid Number of Petroleum Products by Potentiometric Titration or ASTM D 4739, Test Method for Base Number Determination by Potentiometric Titration. Neutralization numbers greater than 0.5 mg KOH per g of crude oil are likely to result in corrosion of carbon steel. Some prefer to use a neutralization number based on the distillate fraction present in the corrosive zone. This results in a critical neutralization number of about 1.5 mg KOH per g [79,20],... 

Therefore, a new stress corrosion cracking test method was developed (Creviced Bent Beam CBB test), which considers the crevice effect as well as factors B, C and D above. Bend test specimens with an artificial crevice made from graphite wool (more sensitive than those made from PETE and especially metal-metal) were tested (both welded and non-welded but sensitised at 600 C/2 h) in high purity water with 0.2 pS/cm, oxygen saturated, chloride < 0.1 mg/1, pH S.8-6.2 at 250 C. For more than 20 steel specimens with different carbon contents (which are responsible for various susceptibilities to sensitisation) one obtains very clear conclusions from 20 specimens each of them showed stress corrosion cracking after only 24 hours, so long as the carbon content lied in the range 0.06-0045%. In the process cracks with... 

Observations on Stress Corrosion Cracking Initiation Sites in Carbon Steel Conference Corrosion 94, Paper No. 234 NACE, Houston, TX, USA, 1994, 13 S. [4 Van der Sluys, W. A. DeMiglio, D. S. Use of a Constant Delta Test Method in the Investigation of Fatigue Crack Growth in 288 deg C Water Environments. Conference Environment-Sensitive Fracture Evaluation and Comparison Test Methods, Gaithersburg, Maryland, USA, 26-28 Apr. 1982... 

Electrochemical corrosion characteristics of iron were determined by potentiodynamic and impedance spectroscopy techniques. Tests were applied to chemically pure iron Fe made by electrocrystalization method and to carbon steel S235JR with the chemical composition shown in Table 3. 

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