Creep properties of PWC-11 base metal and weldments as affected by heat treatment

Cover of: Creep properties of PWC-11 base metal and weldments as affected by heat treatment |

Published by National Aeronautics and Space Administration, For sale by the National Technical Information Service in [Washington, DC], [Springfield, Va .

Written in English

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Subjects:

  • Metals -- Creep.,
  • Electron beam welding.

Edition Notes

Book details

StatementR.H. Titran, T.J. Moore, and T.L. Grobstein.
SeriesNASA technical memorandum -- 88842.
ContributionsMoore, T. J., Grobstein, Toni., United States. National Aeronautics and Space Administration.
The Physical Object
FormatMicroform
Pagination1 v.
ID Numbers
Open LibraryOL18032390M

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Get this from a library. Creep properties of PWC base metal and weldments as affected by heat treatment. [Robert H Titran; T J Moore; T. Grobstein.; United States. National Aeronautics and. Creep behavior of niobium alloy PWC stress was imposed equally on the base metal, weld metal, and heat-affected zone.

Creep Properties of PWC Base Metal and Weldments as Affected by. Creep property of Nb-1ZrC (PWC) alloy showed the better result for electron beam welds as compared to base metal for the two conditions of heat treatment, i.e., annealing and ageing.

The creep rupture test was conducted at the temperature of : Santosh Kumar Gupta, Sanjib Jaypuria, Dilip Kumar Pratihar, Partha Saha. The filler metals varied in creep strength level, so that one overmatched, one undermatched, and one matched the creep strength of the P grade pipe base material.

The long-term objective of this work was to study the influence of weld metal creep strength on the overall creep behavior of the welded joints and their failure mechanism.

A soft zone in Cr-Mo steel weldments has been reported to accompany the infamous Type IV cracking, the highly localized creep damage in the heat-affected zone of creep-resistant steels. A hr, K aging treatment prior to creep testing had a severe detrimental effect on creep strength of the base metal and transverse electron beam weldments, reducing the time to attain 1.

The weld joints exhibited significantly lower creep rupture lives than the base metal at lower applied stresses. Creep rupture location of the weld joints was found to occur in the ICHAZ.

The impact of welding on the creep properties of advanced 9–12% Cr steels and proper heat treatment by the base metal. notch location in distinct weld regions such as weld metal (WM. complex microstructures in weld metals and heat affected zones mean that the properties of the material change from the base metal into the weld [6].

Creep in welds is therefore more complex than creep in base metal and care has to be applied when the process is being modeled. The weld metal and HAZ are frequently referred as steel weldments.

The welding processes, welding consumables, and welding parameters have also influence on these properties. Properties of steel weldments are also influenced by the corrosive atmospheres and cyclic loading to which they are frequently being subjected.

Heat affected zone. the creep strength of the weld joint and the basic material. The following relation is used for this purpose R /t/T R (w)/t/T WSF(t) u = u (2) where WSF(t) is weld strength factor, Ru(w)/t/T is creep strength of the weldment and Ru/t/T is creep strength of the base material at temperature T and time to rupture t.

Creep performance of welded structures at high temperatures M Law, W Payten 2 weld metals, 3 HAZ material properties, 2 different HAZ widths and 4 different levels of imposed axial mismatch between the weld components creep properties, wide heat affected zones, or are assessed as being subject to high imposed axial.

Alternatively, a Post Weld Heat Treatment (PWHT) may be specified to improve the properties of the weld and of the Heat Affected Zone (HAZ). Filler metals are generally similar in composition to the base Creep-resistant-steels, except if post weld heat treatment cannot be performed.

In that case austenitic filler metals (not hardenable) may be. Weld on Publishing, Metals Handbook, Volume 4 – Heat Treating.

9th Edition. American Society for Metals, When determining whether or not to PWHT, the alloying system and previous heat treatment of the base metal must be considered Figure 2. Post heat. The fusion line and HAZ for a weldment between 1CrMoV and 12CrMoV base metals welded with 5CrMoV and 12CrMoV weld metal was analysed for carbon migration in [57 Buchmayr B, Cerjak H, Witmer M, et al.

Carbon diffusion and microstructure in dissimilar Cr-Mo-V-welds and their influence on the mechanical by: 8. In this paper, the effect of postweld heat treatment (PWHT) conditions on mechanical properties of 9Cr-1Mo-V steel welds was investigated. The PWHT conditions are organized with reference to the tempering parameter (Larson-Miller Parameter), with the heat treatment conducted in an LMP range of to × 10 : Tomohiro Tanaka, Masamitsu Abe, Mitsuyoshi Nakatani, Hidenori Terasaki.

The effects of the base metal dissolution, isothermal solidification and post-bond heat treatment on the migration of the main element in the interlayer and base metal were characterized. And a new design method of interlayer composition for TLP bonding superalloy is proposed. PROPOSED GUIDELINES FOR WELDING PROCEDURES TO ENSURE QUALITY WELDING OF CREEP STRENGTH ENHANCED FERRITIC If the specimen breaks in the base metal outside the weld or fusion line, the test shall be accepted as in weld or heat affected zone (HAZ) in any direction on the convex Size: KB.

The sites of base metal, heat affected zone and weld metal for both a C(T) and a circular notched specimens are shown in Fig. 17, Fig. The width of the HAZ is mm and the notch was located at the middle part of the HAZ, which is identical with the actual welded joint specimen. The type of element used is 8-noded element for both by: DESIGN FOR WELDING 3 on metals to highlight the considerations that should be given to the reported values of the properties.4 Only those properties related to weldment design will be dis-cussed in this chapter.

These include the mechanical, physical, and corrosion properties. Linnert, G. E.,Welding Metallurgy, 4th ed., Miami: American. Role of nonlinear fracture mechanics in assessing fracture and crack growth in welds. Mismatch between tensile and creep properties of the base metal and weld metal for the various weldments.

this interface is the fusion line for the undermatched weld metal if one considers the heat-affected zone (HAZ) to be the transitional layer. Cited by:   At 19mm base metal thickness, PWHT will probably be required to keep the base metal hardness below 22 HRc scale for NACE compliance.

What you can do is have a weld coupon completed and evaluate the base metal heat affected zone hardness. Creep properties of weldments should be included in pipeline design. Weld strength and weld strength reduction factors, representing a ratio between creep strength of weld and base material, are possible to use for quantitative expression of welding effect.

This paper reports the investigation of P23 weldment production possibilities. However, the LTT also raised the ductile-brittle transition temperature of the base metal above room temperature. A thermo-mechanical treatment (TMT) has been proposed in the present study as a way of balancing the need for improved creep properties in the weld region and an acceptable level of room temperature ductility in the base by: 1.

Microstructure, including precipitate and tempered martensite, of the base metal and ICHAZ was carefully characterized with advanced microscopy techniques. Creep strength of the simulated ICHAZs was evaluated at a high creep temperature of °C with a stress of MPa.

Some scatter in the tensile properties, of the order of 10%, was noted between the various lots of a given material condition (i.e., base metal, weld metal, and transverse weld samples).

The yield strength data for the weakest heat of base metal, the weakest transverse weld and the weakest weld metal Author: H.E. McCoy, P.L. Rittenhouse. Book: Creep deformation and rupture behavior of Cr-1Mo steel weldments and its constituents (base metal, weld metal and simulated heat affected zones).

Following welding, the weldment was given a renormalizing and tempering heat treatment. Chemical analysis, metallurgical examination, tensile testing and creep rupture testing were performed.

For the weld metal, the carbon content was % and the oxygen content was %. HAZ across the weld metal to the other base plate. These hardness results are partially in good agreement with literature.

Indeed, Gul et al. [2], have found that maxi-mum hardness values are measured in the area of weld metal (WM). But in the present study, the maximum hardness is both in weld metal and heat-affected Size: 2MB. This work is focused on testing and evaluation of creep properties of P92 base material (BM) and welded joints (WJ) as well.

Up to date results of creep rupture test of P92 base metal and w elds are presented in this article. Creep rupture strength (CRS) of WJ initially reaches values close to the BM, with longer times to fracture and especially at.

@article{osti_, title = {The effect of heat treatment on the microstructure and creep rupture properties of 9CrMoW steel}, author = {Nickel, H and Research Centre Juelich and Ennis, P J and Wachter, O}, abstractNote = {The effects of austenitizing at temperatures in the range to 1, C and of tempering at temperatures in the range to C on the microstructure and.

Depending on original heat treatment, creep damage progression is known to be accelerated by the mismatch in properties of the base metal, weld deposit, and heat affected zone (HAZ). This mismatch results in stress intensification that can accelerate creep damage near a weldment (typically in or adjacent to the HAZ).Author: Phillip E.

Prueter. The creep-rupture properties of weld metal, transverse weldments, and base metal showed an effect of carbon that depended on temperature. At C ( F), the percent C steel had the highest strength, while the strength of the other two steels were similar.

Creep deformation and creep strength are a grain-size sensitive property. Thus a larger grain size improves creep strength. For austenitic stainless steels, SA TPH for example, the code requires a grain size of #7 or coarser, to assure adequate creep strength.

The elevated temperatures where creep occurs lead to other microstructural changes. Creep occurs faster at higher temperatures. However, what constitutes a high temperature is different for different metals. When considering creep, the concept of anhomologous temperature is useful.

The homologous temperature is the actual temperature divided by the melting point of the metal, with both being expressed in K. In general,File Size: 1MB. significant modifications to the material properties in the area around the weld.

The area impacted by the heat input from the welding process is termed as heat-affected zone or HAZ. For high-strength 5xxx and 6xxx-series alloys joined by fusion welding, the HAZ is typically 30%% weaker than the base File Size: KB. Always check weld metal and base metal strength.

Smaller value governs. In most cases, the weld metal strength will govern. In weld design problems it is advantageous to work with strength per unit length of the weld or base metal. Limitations on weld dimensions (See AISC Spec. Jb on page of manual) Minimum size (amin).

Welding-heat-resisting materials is important for Hot Service Applications. Although different, Nickel and Cobalt base alloys are sometimes grouped together, when considering welding.

That is because they are used for heat resistant and for corrosion resistant applications. In wrought form they present no special welding problems, with due attention.

In the weld metal and part of the heat-affected zone (HAZ), where the α→γ→α transformation occurred, the proportion of martensite is always considera b l e ; therefore, during welding, a certain risk of cracking may need to be considered.

As a consequence of these arguments, welding engineers may need to have a. non-standard ferritic stainless steels. They are characterized by weld and HAZ grain growth which can result in low toughness of welds.

To weld the ferritic stainless steels, filler metals should be used which match or exceed the Cr level of the base alloy. Type is available as metal cored wire and Type is available in all forms.

Austenitic. Additionally, depending on original heat treatment, creep damage progression is known to be accelerated by the mismatch in creep properties of the base metal, weld deposit, and heat affected zone (HAZ).Author: Phillip E. Prueter, Jonathan D. Dobis, Mark S.

Geisenhoff, Michael S. Cayard.CREEP • Creep occurs even with high strength materials with high heat resistant. • At high temperature atomic bonding starts to fail, causing movement of atoms and atomic planes. • Restructuring of atoms also occur at high temperature. • Movements of dislocations also more likely at File Size: KB.Know the Important Welding-properties.

Welding-properties are strength, hardness, ductility, fracture toughness. However, in specific cases, properties may change: depending on welding history, and on the presence of certain factors, catastrophic failures may occur because of brittleness, stress raisers, triaxial stresses, nil ductility.

Below transition temperature, and lacking crack.

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