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Carbon and Low-alloy Steels

These usually present little problem since the parent and filler metals are generally of similar composition, although there is some evidence that the precise electrode type in manual metal arc welding for marine conditions may be important weld metal deposited from basic-coated rods appears to corrode more rapidly than that deposited from rutile-based coatings. [Pg.409]

Parent metal Filler metal Other factors [Pg.410]

State of heat treatment Toughness Degree of restraint [Pg.410]

Toughness Hydrogen content Form factor (Transition) [Pg.410]

Purity Homogeneity Homogeneity Electrode diameter (Heat input during welding) Skill and reliability of the welder [Pg.410]

The largest group of steels produced both by number of variants and by volume is that of carbon and low-alloy steels. It is characterized by the fact that most of the phase relations and phase transformations may be referred to the binary Fe—C phase diagram or comparatively small deviations from it. These steels are treated extensively in [1.80]. [Pg.227]

According to the effect of carbon concentration on the phases formed and on their properties. Fig. 3.1-109 shows the variation of the effective average mechanical properties of as-rolled 25-mmbars of plain carbon steels as an approximate survey of the typical concentration dependence. [Pg.227]

Carbon steels are defined as containing up to 1 wt% C and a total of 2 wt% alloying elements. Apart from the deoxidizing alloying elements Mn and Si, two impurity elements are always present in carbon steels phosphorous and sulfur. Phosphoms increases strength [Pg.227]

A survey of the alloying elements used and of the ranges of composition applied in carbon and low-alloy steels may be gained from the SAE-AISI system of designations for carbon and alloy steels listed in Table 3.1-43. Extensive cross references to other standards may be found in [1.81]. [Pg.227]

Designation UN number SAE-AISI number Cast or heat chemical rangt C s and limits (wt%) Mn Pmax S max [Pg.228]

This group of steels are used in industry extensively. The versatility and low cost are attractive features. As opposed to pure iron, alloying iron with small amounts of carbon results in improved strength and hardness without loss of ductility. These alloys are attractive from the points of view such as ease of fabrication, machinability and welding as well as good corrosion resistance. [Pg.202]

Some important considerations in the selection of steels are detailed below  [Pg.202]

Steel used in thick sections Steels with small grain size [Pg.202]

Absence of interstitial impurities Northern pipelines Steels with low brittle to ductile [Pg.202]

Thick plate (2 in) Stress relief is necessary consideration of the effect of triaxiality on fracture toughness [Pg.203]

Smelting of iron to extract it from its ore is believed to have started around 1300 BC in Palestine. Tools of iron appeared about this time and an iron furnace has been found. Steel is basically an alloy of iron and carbon with the carbon content up to approximately 2 wt%. [Pg.67]

because of its strength, formability, abundance, and low cost is the primary metal used for structural applications. As the term plain carbon steel implies, these are alloys of iron and carbon. These steels were the first developed, are the least expensive, and have the widest range of applications. [Pg.67]

The presence of carbon, without substantial amounts of other alloying elements, is primarily responsible for the properties of carbon steel. However, manganese is present to improve notch toughness at low temperatures. The steels discussed in this chapter contain less than 0.35% carbon to make them weldable. [Pg.67]

Weathering steels that contain small additions of copper, chromium, and nickel to form a more adherent oxide during atmospheric exposures. An example is U.S. Steel s Cor-Ten steel. [Pg.67]

Hardenable steels that offer higher strength and hardness after proper heat treatment and which contain additions of chromium or molybdenum and possibly nickel. Common examples include 4130 and 4340 steels. [Pg.67]


Plain Carbon and Low Alloy Steels. For the purposes herein plain carbon and low alloy steels include those containing up to 10% chromium and 1.5% molybdenum, plus small amounts of other alloying elements. These steels are generally cheaper and easier to fabricate than the more highly alloyed steels, and are the most widely used class of alloys within their serviceable temperature range. Figure 7 shows relaxation strengths of these steels and some nickel-base alloys at elevated temperatures (34). [Pg.117]

Subsection C This subsection contains requirements pertaining to classes of materials. Carbon and low-alloy steels are governed by Part UCS, nonferrous materials by Part UNF, high-alloy steels by Part UHA, and steels with tensile properties enhanced by heat treatment by Part UHT. Each of these parts includes tables of maximum allowable stress values for all code materials for a range of metal temperatures. These stress values include appropriate safety fac tors. Rules governing the apphcation, fabrication, and heat treatment of the vessels are included in each part. [Pg.1025]

Vessels for high-temperature serviee may be beyond the temperature hmits of the stress tables in the ASME Codes. Sec tion TII, Division 1, makes provision for construction of pressure vessels up to 650°C (1200°F) for carbon and low-alloy steel and up to 815°C (1500°F) for stainless steels (300 series). If a vessel is required for temperatures above these values and above 103 kPa (15 Ibf/in"), it would be necessaiy, in a code state, to get permission from the state authorities to build it as a special project. Above 815°C (1500°F), even the 300 series stainless steels are weak, and creep rates increase rapidly. If the metal which resists the pressure operates at these temperatures, the vessel pressure and size will be limited. The vessel must also be expendable because its life will be short. Long exposure to high temperature may cause the metal to deteriorate and become brittle. Sometimes, however, economics favor this type of operation. [Pg.1028]

The cathodic protection of plain carbon and low-alloy steels can be achieved with galvanic anodes of zinc, aluminum or magnesium. For materials with relatively more positive protection potentials (e.g., stainless steels, copper, nickel or tin alloys), galvanic anodes of iron or of activated lead can be used. [Pg.180]

Table 16-2 Protection potential regions for plain carbon and low-alloy steels (YP 800 N mm ) for marine structures... Table 16-2 Protection potential regions for plain carbon and low-alloy steels (YP 800 N mm ) for marine structures...
Stress corrosion can arise in plain carbon and low-alloy steels if critical conditions of temperature, concentration and potential in hot alkali solutions are present (see Section 2.3.3). The critical potential range for stress corrosion is shown in Fig. 2-18. This potential range corresponds to the active/passive transition. Theoretically, anodic protection as well as cathodic protection would be possible (see Section 2.4) however, in the active condition, noticeable negligible dissolution of the steel occurs due to the formation of FeO ions. Therefore, the anodic protection method was chosen for protecting a water electrolysis plant operating with caustic potash solution against stress corrosion [30]. The protection current was provided by the electrolytic cells of the plant. [Pg.481]

CLOSED DIE FORGING PROCESS CAPABILITY MAP FOR LOW TO MEDIUM CARBON AND LOW ALLOY STEELS... [Pg.218]

To avoid decarburization and Assuring of the carbon and low-alloy steels, which is cumulative with time and, for all practical purposes irreversible, the limitations of the Nelson Curves should be followed religiously, as a minimum. Suitable low-alloy plate materials include ASTM-A204-A, B, and C and A387-A, B, C, D, and E, and similarly alloyed materials for pipe, tubes, and castings, depending upon stream temperatures and hydrogen partial pressures, as indicated by the Nelson Curves. [Pg.258]

Temperatures required for corrosion by naphthenic acids range from 450 to 750°F, with maximum rates often occurring between 520 and 535°F. Whenever rates again show an increase with a rise in temperature above 650°F, sueh increase is believed to be caused by the influence of sulfur compounds which become corrosive to carbon and low alloy steels at that temperature. [Pg.264]

For erosive wear. Rockwell or Brinell hardness is likely to show an inverse relation with carbon and low alloy steels. If they contain over about 0.55 percent carbon, they can be hardened to a high level. However, at the same or even at lower hardness, certain martensitic cast irons (HC 250 and Ni-Hard) can out perform carbon and low alloy steel considerably. For simplification, each of these alloys can be considered a mixture of hard carbide and hardened steel. The usual hardness tests tend to reflect chiefly the steel portion, indicating perhaps from 500 to 650 BHN. Even the Rockwell diamond cone indenter is too large to measure the hardness of the carbides a sharp diamond point with a light load must be used. The Vickers diamond pyramid indenter provides this, giving values around 1,100 for the iron carbide in Ni-Hard and 1,700 for the chromium carbide in HC 250. (These numbers have the same mathematical basis as the more common Brinell hardness numbers.) The microscopically revealed differences in carbide hardness accounts for the superior erosion resistance of these cast irons versus the hardened steels. [Pg.270]

Nickel and nickel alloys possess a high degree of resistance to corrosion when exposed to the atmosphere, much higher than carbon and low-alloy steels, although not as high as stainless steels. Corrosion by the atmosphere is, therefore, rarely if ever a factor limiting the life of nickel and nickel alloy structures when exposed to that environment. [Pg.785]

Compared with ferritic carbon and low-alloy steels, relatively little information is available in the literature concerning stainless steels or nickel-base alloys. From the preceding section concerning low-alloy steels in high temperature aqueous environments, where environmental effects depend critically on water chemistry and dissolution and repassivation kinetics when protective oxide films are ruptured, it can be anticipated that this factor would be of even more importance for more highly alloyed corrosion-resistant materials. [Pg.1306]

The effects of hydrogen on carbon and low-alloy steel equipment ... [Pg.36]

Materials selection for low-temperature service is a ecialized area. In general, it is necessary to select materials and fabrication methods which will provide adequate toughness at all operating conditions. It is frequently necessary to specify Charpy V-notch (or other appropriate) qualification tests to demonstrate adequate toughness of carbon and low-alloy steels at minimum operating temperatures. [Pg.45]

Corrosion is normally associated with aqueous solutions but oxidation can occur in dry conditions. Carbon and low alloy steels will oxidise rapidly at high temperatures and their use is limited to temperatures below 500°C. [Pg.291]

The corrosion allowance is the additional thickness of metal added to allow for material lost by corrosion and erosion, or scaling (see Chapter 7). The allowance to be used should be agreed between the customer and manufacturer. Corrosion is a complex phenomenon, and it is not possible to give specific rules for the estimation of the corrosion allowance required for all circumstances. The allowance should be based on experience with the material of construction under similar service conditions to those for the proposed design. For carbon and low-alloy steels, where severe corrosion is not expected, a minimum allowance of 2.0 mm should be used where more severe conditions are anticipated this should be increased to 4.0 mm. Most design codes and standards specify a minimum allowance of 1.0 mm. [Pg.813]

The amount of hydrogen partial pressure reduction depends upon the materials and the relative thickness of the cladding/ weld overlay and the base metal—the thicker the stainless barrier is relative to the base metal the better.32 Archakov and Grebeshkova33 mathematically considered how stainless steel corrosion barrier layers increase resistance of carbon and low alloy steels to high temperature hydrogen attack. [Pg.10]

This recommended practice summarizes the results of experimental tests and actual data acquired from operating plants to establish practical operating limits for carbon and low alloy steels in hydrogen service at elevated temperatures and pressures. The effects on the resistance of steels to hydrogen at elevated temperature and pressure that result from high stress, heat treating, chemical composition, and cladding are discussed. [Pg.30]

A 350 Carbon and Low-Alloy Steel Forgings Requiring Notch Toughness Testing for Piping... [Pg.26]

Minimum Energy Requirements. Except for bolting materials, the applicable minimum energy requirements for carbon and low alloy steels with specified minimum tensile strengths less than 656 MPa (95 ksi) shall be those shown in Table GR-2.1.3(e). [Pg.36]

Lateral Expansion Requirements. Other carbon and low alloy steels having specified minimum tensile strengths equal to or greater than 656 MPa (95 ksi), all bolting materials, and all high alloy steels (P-Nos. 6, 7, and 8) shall have a lateral expansion opposite the notch of not less than 0.38 mm (0.015 in.) for all specimen sizes. The lateral expansion is the increase in width of the broken impact specimen over that of the unbroken specimen measured on the compression side, parallel to the line constituting the bottom of the V-notch (see ASTM A 370). [Pg.36]

N = equivalent number of full displacement cycles during the expected service life of the piping system.5 N shall be increased by a factor of 10 for all materials that are susceptible to hydrogen embrittlement (carbon and low alloy steels) when the system design temperature is within the hydrogen embrittlement range [up to 150°C (300°F)]. [Pg.90]

Table PL-2.5.2 Thermal Expansion of Carbon and Low Alloy Steel... Table PL-2.5.2 Thermal Expansion of Carbon and Low Alloy Steel...
Carbon and low alloy steel pressure retaining parts applied at a specified minimum design metal temperature (2.11.4.5) between -30°C (-20°F) and 40°C (100°F) shall require impact testing in accordance with 2.11.4.3.1 and 2.11.4.3.2. [Pg.41]


See other pages where Carbon and Low-alloy Steels is mentioned: [Pg.95]    [Pg.211]    [Pg.226]    [Pg.386]    [Pg.2419]    [Pg.2450]    [Pg.96]    [Pg.64]    [Pg.471]    [Pg.1300]    [Pg.1307]    [Pg.36]    [Pg.89]    [Pg.91]    [Pg.6]    [Pg.289]    [Pg.8]    [Pg.9]    [Pg.10]    [Pg.37]    [Pg.231]    [Pg.231]    [Pg.232]    [Pg.41]   
See also in sourсe #XX -- [ Pg.506 ]




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Steel low-alloyed

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