Characterization of low cycle fatigue damage in 9Cr–1Mo ferritic steel using X-ray diffraction technique

Rai, Sanjay; Choudhary, B.K.; Jayakumar, T.; Rao, K. Bhanu Sankara; Raj, Baldev

doi:10.1016/s0308-0161(98)00140-9

Cited by 38 publications

(10 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Typically, an increase in stacking faults and structural disorders widens the XRD peaks, and the presence of tensile stress causes an increase in the FWHM, with relaxation processes typically decreasing its magnitude. 20,21 After unloading, the FWHM of ferrite remained the same as the last straining step, whereas the FWHM increased in the austenite indicating accommodation of plastic strain in the austenite.…”

Section: Xrd Surface Stress Determinationmentioning

confidence: 96%

An experimental investigation into strain and stress partitioning of duplex stainless steel using digital image correlation, X-ray diffraction and scanning Kelvin probe force microscopy

Örnek

Engelberg

2016

The Journal of Strain Analysis for Engineering Design

View full text Add to dashboard Cite

The evolution of microstructure strain partitioning during quasi in situ tensile loading of grade 2205 duplex stainless steel has been investigated. Digital image correlation revealed the development of tensile strain initially in austenite and at interphase boundaries, and further extending into the ferrite with increasing load. Higher resolution digital image correlation observations indicated strain hardening of austenite, followed by deformation of the ferrite. Digital image correlation analysis of a 20% cold-rolled microstructure revealed tensile strain development at interphases, with discrete tensile and compressive strain pockets observed within the austenite. X-ray diffraction measurements indicated the presence of tensile stresses primarily developing in the ferrite, with full-width at half maximum values indicating plastic strain accumulation primarily in the austenite. The effect of tensile loading on Volta potential differences, obtained via scanning Kelvin probe force microscopy, highlighted the development of discrete anodic and cathodic sites with the introduction of strain. A Volta potential roughness parameter (C Ra) is introduced describing Volta potential changes as a function of strain. This observation supports the concept of an enhanced propensity of local electrochemical activity with increasing applied strain in duplex stainless steel.

show abstract

Section: Xrd Surface Stress Determinationmentioning

confidence: 96%

An experimental investigation into strain and stress partitioning of duplex stainless steel using digital image correlation, X-ray diffraction and scanning Kelvin probe force microscopy

Örnek

Engelberg

2016

The Journal of Strain Analysis for Engineering Design

View full text Add to dashboard Cite

show abstract

“…The FWHM of the diffraction peaks may be related to various material properties, such as grain distortion, dislocation density, and residual stresses [ 22 ]. The increase in FWHM and the widening of the X-ray peak were associated with an increase in the stacking faults and structural disorder, alongside the presence of tensile stress in the material, while a relaxation of the tensile stress decreased the FWHM [ 23 ]. The linear increase in the FWHM of the XRD peak was also related to increases in the hardness and density of the point defects that alter the crystallinity and grain boundary mobility [ 24 ].…”

Section: Resultsmentioning

confidence: 99%

Microstructural and Mechanical Properties of Novel Co-Free Maraging Steel M789 Prepared by Additive Manufacturing

Brytan

Król

Benedyk³

et al. 2022

Materials

View full text Add to dashboard Cite

This research aims to characterize and examine the microstructure and mechanical properties of the newly developed M789 steel, applied in additive manufacturing. The data presented herein will bring about a broader understanding of the processing–microstructure–property–performance relationships in this material based on its chemical composition and heat treatment. Samples were printed using the laser powder bed fusion (LPBF) process and then the solution was annealed at 1000 °C for 1 h, followed by aging at 500 °C for soaking times of 3, 6 and 9 h. The AM components showed a relative density of 99.1%, which arose from processing with the following parameters: laser power of 200 W, laser speed of 340 mm/s, and hatch distance of 120 µm. Optical and electron microscopy observations revealed microstructural defects, typical for LPBF processes, like voids appearing between the melted pools of different sizes with round or creviced geometries, nonmelted powder particle formation inside such cavities, and small spherical porosity that was preferentially located between the molten pools. In addition, in heat-treated conditions, AM maraging steel has combined oxide inclusions of Ti and Al (TiO2:Al2O3) that reside along the grain boundaries and secondary porosities; these may act as preferential zones for crack initiation and may increase the brittleness of the AM steel under aged conditions. Consequently, the elongation of the AM alloy was low (<3%) for both annealed and aged solution conditions. The tensile strength of AM M789 increased from 968 MPa (solution annealed) to 1500–1600 MPa after the aging process due to precipitation within the intermetallic η-phase. A tensile strength and yield point of 1607 ± 26 and 1617 ± 45 MPa were obtained, respectively, after a full heat treatment at 500 °C/6 h. The results show that 3 h aging of solution annealed AM M789 steel achieves satisfactory material properties in industrial practice. Extending the aging time of printed parts to 6 h yields slightly improved properties but may not be worth the effort, while long-term aging (9 h) was shown to even reduce quality.

show abstract

“…The ratio between the I/FWHM of calcite and quartz was also calculated as follows: R Cc/Qz = (I Cc (10-14) /FWHM Cc (10-14) )/(I Qz (10-11) /FWHM Qz (10)(11) ). The relationship between FWHM and material hardness is a standard approach in material science (Rai et al, 1999;Vashista and Paul, 2012;Fu et al, 2018) and was assessed using the R Cc/Qz ratio for V. nigrescens, V. muralis and block core samples by a Pearson correlation analysis (PAST 4.05). For each sample series, the I/FWHM percentage variation of each calcite peak obtained for V. nigrescens and V. muralis with respect to the core was calculated and visualized using a Principal Coordinate Analysis plot (PCoA; symmetric scaling, centring samples by samples, centring species by species, performed using CANOCO 4.5, Ter Braak and Šmilauer, 2002).…”

Section: X-ray Powder Diffractionmentioning

confidence: 99%

Lichen impact on sandstone hardness is species‐specific

Tonon

Bernasconi

Martire

et al. 2022

Earth Surf Processes Landf

View full text Add to dashboard Cite

The balance between lichen biodeterioration and bioprotection processes on stone surfaces depends on many variables and is crucial to understanding the role of lichens in biogeomorphology and their threat to stone heritage conservation. However, stones colonized by lichens have still been mostly examined in terms of affected volumes and physico-chemical modes of interactions, overlooking the overall effects on properties related to surface durability. In this study, the impact of lichen colonization patterns on Cortemilia sandstone was examined beneath thalli of three lichen species. Rock hardness, a proxy for rock durability, was measured at different depths from the surface using an Equotip hardness tester and compared to that of freshly cut surfaces and exposed surfaces uncolonized by lichens. Mineralogical analyses were performed by X-ray powder diffraction on rock beneath lichen colonization, in comparison with unweathered rock. Equotip analyses quantified a differential, species-specific decrease in stone hardness. This variability was related to differences in hyphal penetration patterns and, possibly, calcite (re-)precipitation. In particular, in the case of the species most impacting rock hardness, X-ray diffraction patterns of calcite showed a remarkable stability of crystallographic plane (01-12), known to be enhanced in the presence of organic chelants. These results confirm that decisions on lichen removal from stone surfaces should consider species-specific behaviour. Moreover, the innovative approach of measuring stone hardness variation in association with the analysis of biomineralization processes contributes to unveil the extension of the sphere of lichen interaction within the stone substrate beyond the limit of the hyphal penetration.

show abstract

Characterization of low cycle fatigue damage in 9Cr–1Mo ferritic steel using X-ray diffraction technique

Cited by 38 publications

References 12 publications

An experimental investigation into strain and stress partitioning of duplex stainless steel using digital image correlation, X-ray diffraction and scanning Kelvin probe force microscopy

An experimental investigation into strain and stress partitioning of duplex stainless steel using digital image correlation, X-ray diffraction and scanning Kelvin probe force microscopy

Microstructural and Mechanical Properties of Novel Co-Free Maraging Steel M789 Prepared by Additive Manufacturing

Lichen impact on sandstone hardness is species‐specific

Contact Info

Product

Resources

About