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Dissimilar transient liquid phase (TLP) bonding between stainless steel 310 and Inconel 617 was carried out using a BNi-2 interface layer. TLP joints were fabricated at 1040, 1070 and 1100 °C for a bonding time of 60 min. In addition to microstructural evaluations, the mechanical properties of different TLP joints were also studied. The results indicated that increasing the bonding temperature resulted in decreasing the solidification zones and accelerating the formation of the intermetallic compounds. Among different TLP joints, the joint fabricated at 1040 °C exhibited the highest shear strength of 611 MPa. SEM investigations of the fractured surfaces revealed that the formation of higher amount of intermetallic compounds at higher temperatures deteriorated the shear strength of the Inconel 617/Stainless Steel 310 TLP joint.

The present work focuses on the enhancement of the antireflective property of black coatings produced on 310-grade stainless steel by hot conversion coating techniques. The optimum process parameter has been determined by using Taguchi L9 orthogonal array. Coating duration (d) and bath temperature (t) were selected as control variables (process parameters). The percentage reflectance (%R) was considered response characteristics. To analyze the effect of each process parameter on percentage reflectance, Taguchi analysis, ANOVA, main effect plots, interaction plots, and contour plots were considered. It has been found that 1100 g/L potassium hydroxide, 200 g/L of potassium nitrate, 40-minute duration of coating, and 140 °C bath temperature produces coating with lowest average percentage reflectance (%R). The characterization of coated samples was done by scanning electron microscope (SEM). The surface morphological studies revealed that a uniform coating with a wavy structure act as a good light absorber in the visible region of 350–800 nm.

Shielded metal (SM) and Gas tungsten (GT) arc welding of two different sheet metal grades of stainless steel 310 and 304 of 3 mm thickness is attempted to produce a sound weld. The single and double ‘V’ butt joint is made to find its suitability for the anticipated use by producing the differences in strength in the welded joints. Two gas tungsten arc welded butt joint is produced by choosing the current as 110 A and voltage 19 V. Two shielded metal arc welded butt joints are produced when the current is kept as 80 A and voltage 19 V. The welded specimens are evaluated by dye penetrant inspection to identify the weld defects. From the inspection weld specimens are found defect free from porosity, cracks, lack of penetration and etc. The welded specimens are undergone for tensile testing and found as maximum 594 MPa in the case double ‘V’ shielded metal arc welded butt joint and 556 MPa in the case of double ‘V’ butt joint by the gas tungsten arc welding process. The research work will be suitable to choose effective welding technique for the butt welding of dissimilar alloys of stainless-steel grades 310 and 304 of 3 mm thickness with single or double ‘V’ edges for the practical use.

A nested neutron spectrometer was used to measure the stray neutron fluence and ambient dose equivalent produced by protons from a 4 MV tandem accelerator on various target materials at the Reactor Materials Testing Laboratory (RMTL), Queen's University, Kingston, Ontario. The nested neutron spectrometer utilizes a Helium-3 proportional counter and measures the thermal neutron count rate as a function of moderator shell-thickness. Using custom unfolding software, neutron spectra and neutron dosimetric quantities were derived at various locations within the RMTL. The nested neutron spectrometer can be operated in both a pulse mode and current mode allowing for measurements over a wide range of accelerator beam currents. All measurements conducted at the facility were within the main accelerator chamber and experimental target rooms. Target room measurements were conducted with a variety of target materials representative of those to be used for research planned at the RMTL.

A transient thermo-mechanical model is employed to study the effects of welding parameters on the occurrence of solidification cracking. A finite element program, ANSYS, is employed to solve the thermal and mechanical equations while the different variables such as welding current, speed and sequence are considered in the simulation. The studied geometry was butt joint of two stainless steel plates with the thickness of 2 mm. Then, the samples were welded by TIG method without filler. To verify the numerical results, the model outputs were checked with the experimental observations and good agreement was observed. It was found that the increasing of welding current from 70 A to 100 A resulted in the increase in transverse tensile strain from 1.2 to 2.1 which can facilitate the occurrence of solidification cracking. Furthermore, the application of symmetric welding layout is an effective method to prevent solidification cracking.

In this study, standard stainless steel 310, modified 310 with Al and Ti and aluminised 310 were tested in supercritical water (SCW) at 500°C for 1555 h. Weight change measurement and microstructure analysis were carried out to evaluate the corrosion behaviour of these alloys and surface oxide formation in SCW. After 1555 h of SCW exposure, all modified and aluminised samples showed higher weight gain than 310, although weight loss commenced after 887 h for the aluminised samples. Al addition contributed to more surface spinel formation while Ti reduced spinel on the surface and helped form more uniform and dense surface oxide structure. In addition to higher weight gain and subsequent weight loss, aluminised samples also suffered from surface cracking, suggesting that high Al and low Cr surface content is not beneficial for SCW application.

Various methods are employed to produce premium line of cutting tool materials with enhanced mechanical properties and improved service life. Cryogenic Treatment is one of those methods which has been considered for its benefits as a suitable add-on process. In this experimental investigation, Coated Tungsten-Carbide (KC9225) was taken as the cutting tool material and it was subjected to Deep Cryogenic-Treatment to analyse the several changes that might have taken place in its behaviour before and after the treatment. The treatment was carried out by a Dip-Stick arrangement where the temperature was gradually brought down to 100 K at the rate of ± 2 K/min. Tempering was also performed using the Dilatometer and the temperature was raised (~2 K/min) to 473 K. The changes in its mechanical properties both qualitatively as well quantitatively were investigated. Machining performance of the tool was also studied by performing wet turning on Austenitic Stainless Steel-310 where cutting force values were found to reduce by 3 to 71% in different cases thus proving its superiority as compared to the untreated tool.

Extensive precipitation can occur in high temperature materials during service. This is known to significantly affect the mechanical properties. To be able to study this phenomenon, particle formation in the austenitic stainless steel 310 has been quantified. In particular, σ-phase and M23C6-carbides have been analysed. Specimens have been aged up to 5000 h at 800°C.The precipitation of the two phases has been modelled. The basis of the model is diffusioncontrolled growth. σ-phase shows a spherical growth and an M23C6 planar growth. The soft impingement of the diffusion zones with respect to both chromium and carbon is taken into account.The influence on mechanical properties is analysed in a parallel paper.

In this study, aluminized and NiCrAlY plasma-sprayed AISI 310 stainless steel samples were tested in supercritical water (SCW) at 500°C. The microstructure after SCW exposure was analyzed using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD). Weight measurements were taken before and after exposure to provide quantitative comparison of the two coatings on AISI 310 base metal. The results showed that aluminized and bare 310 stainless steel experienced similar weight gain, in the range of 0.02–0.08 mg/cm2 after 1550 hr. The aluminized sample had a slight weight decrease as exposure progressed. Oxide formation, in the forms of Al2O3 and (Fe,Cr)2O3, was found on the aluminized surface along with surface cracking after 1550 hr testing in SCW. NiCrAlY-coated 310, however, had the most consistent weight increase and oxide formation (mainly Al2O3) on the surface. Based on the results from this study, the aluminized coating has limitations in providing surface protection due to surface cracking and weight loss. The NiCrAlY plasma-sprayed coating with alumina formation on the surface has the potential to provide long-term surface protection to the substrate material in SCW.

Intense precipitation may occur in high-temperature materials during service. This precipitation significantly affects the mechanical properties. Coarse precipitates can reduce ductility and toughness dramatically. To investigate the phenomenon, precipitation in the austenitic stainless steel AISI 310 is quantified in a parallel paper. The samples were aged up to 5000 h at 800°C. Especially, σ-phase and M23C6-carbides were analysed.A model for the influence of coarse particles on ductility has been developed and successfully applied to the measured values. A model due to Chen and Mott has been used to compute the effect of particles on toughness. A satisfactory agreement with the observations was obtained.

Flash methods have become one of the most commonly used techniques for measuring the thermal diffusivity and thermal conductivity of various kinds of solids and liquids such as metals, carbon materials, ceramics, and polymers. Easy sample preparation, small sample dimensions, fast measurement times, and high accuracy are only some of the advantages of this non-destructive measurement technique. However, the accuracy of measurement and level of uncertainty of the resulting data are becoming increasingly important for countless industrial applications. Instruments must be checked to determine the uncertainty of the system at different temperature and application ranges. One way of checking the accuracy of the results is to cross-check the unit with certified reference materials. However, there is a lack of standard materials for thermal diffusivity/thermal conductivity all over the world. Furthermore, for some available standards, the thermophysical properties are known only over a limited temperature range. Presented in this work are thermophysical property measurements on a certified thermal conductivity standard, Stainless Steel 310. Tests were carried out between −125 and 1000°C.

The aluminized coating on type 310 stainless steel prepared by high-activity Al pack cementation method has been annealed at 900 °C for 12 h to transform the brittle δ-Fe2Al5 phase into the more ductile β-FeAl phase. The microstructure is studied in detail with transmission electron microscopy. The thick outer layer has β-(Fe, Ni)Al as matrix with cube-like Cr2Al precipitates. The interfacial layer has a thin layer of metastable FCC phase (layer I) and then mixed β-(Fe, Ni)Al grains and α-(Fe, Cr) grains (layers II and III). The Cr2Al precipitates are present in the β-(Fe, Ni)Al grains in layer II but not in those in layer III, while β-FeAl precipitates are present in the α-(Fe, Cr) grains in both layers. The orientation relationships between various phases, the formation of the layers, and the precipitation of Cr2Al in β-(Fe, Ni)Al are discussed.

New ternary compound crystals of (Cr0.45Fe0.55)5Si3 have been obtained by vapour phase siliconizing of SUS 310 plate; the growth conditions and some of the properties of this material were examined. Hollow pillar crystals of 3–5 mm in length and 0.15–0.35 mm in thickness were easily obtained at 1000–1100°C for 1 h. The crystals were much more corrosion resistant against concentrated HCl solutions than SUS 310 plate.

This work aims at the analysis and optimization of joining similar grades of stainless steel by TIG welding. The parameters like current, filler materials, welding speed are the variables in the study. The mechanical properties and microstructure of 310 austenitic stainless steel welds are investigated, by using stainless steel filler material of different grades. Higher tensile strength was achieved with a current 120A and 309L filler rod and also the weld has fewer defects.

During service at elevated temperatures extensive formation of particles can take place that can have adramatic influence on mechanical properties. Precipitation of ?-phase and M23C6-carbides have been studiedboth experimentally and with thermodynamic modelling for 25Cr20Ni austenitic stainless steels (AISI 310) at800 ºC for up to 5000 h. Previous work has demonstrated that the modelling could describe the nucleation andgrowth satisfactory. After long term ageing the particles form bands in the microstructure. In the present paperthe influence of these bands on ductility and toughness at room temperature is analysed. For this purposepreviously developed models for ductility and toughness are utilised. Model values for banded and non-bandedmicrostructures have been generated for casts of 310 in fine and coarse grained conditions with 0.04 and0.12%N. The model values show that in the coarse grained condition, no reduction in ductility and toughnesscan be expected in the banded microstructure. In the fine grained condition a modest reduction is predicted.