Effects of Nitrogen Ion Implantation in 304 Stainless Steel at High Temperatures

1989 ◽  
Vol 157 ◽  
Author(s):  
Sadhna Shrivastava ◽  
Ram D. Tarey ◽  
M.C. Bhatnager ◽  
Amttaeh Jain ◽  
K.L. Chopra
Keyword(s):  
Stainless Steel ◽  
Oxide Layer ◽  
Depth Profiling ◽  
304 Stainless Steel ◽  
Beam Power ◽  
Target Temperature ◽  
X Ray Diffraction ◽  
Glancing Angle ◽  
Nitrogen Ion ◽  
Complete Precipitation

ABSTRACTWe studied the effect of varying the target temperature (by changing the beam power) on the structure and properties of nitrogen ion implanted 304 stainless steel. With a beam power of 0.1 W/ cm2 the target temperature is restricted to 150°C. After a dose of 3. 5x1017N2+/cm2 the microhardness measured at 10g increases by 15%. With a beam power of 1.1 W/cm2 the target temperature is 500°C. After the same dose as before, the irdcrohardness increase is 40%. Glancing Angle X-ray Diffraction and Auger depth profiling results suggest that the increased hardness is due to the presence of nitrogen in solution as opposed to complete precipitation. A sample deformed by compression formed an enhanced oxide layer during implantation. This oxide layer appears to have a capping action against the out-diffusion of nitrogen.

scholarly journals The Atmosphere’s Effect on Stainless Steel Slabs’ Oxide Formation in a CH4-Fuelled Reheating Furnace

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 621
Author(s):  
Aleksi Laukka ◽  
Eetu-Pekka Heikkinen ◽  
Timo Fabritius
Keyword(s):  
Stainless Steel ◽  
Oxide Layer ◽  
Depth Profiling ◽  
Layer Growth ◽  
304 Stainless Steel ◽  
Oxide Growth ◽  
Breakaway Oxidation ◽  
Positive Effects ◽  
Steel Slab ◽  
Single Temperature

Utilising the oxyfuel practice for CH4-fuelled combustion has positive effects on the emissions, efficiency and cost of high temperature furnace practices. However, especially in older installations, oxyfuel usage requires retrofitting and alters the atmosphere in which the oxidation of the steel occurs, when compared to using air as the oxidiser. Stainless steel slab oxide growth during reheating was studied in different atmospheres. The simulated post-burn atmospheres from oxyfuel, lean oxyfuel and air-fuel practices were used to compare oxide-scale layer growth and morphology during simulated typical AISI 304 stainless steel slab reheating prior to hot rolling. Thermogravimetric measurements, glow discharge optical emission spectrometer (GDOES) and field-emission scanning electron microscope energy dispersive X-ray (FESEM-EDS) methodology were applied to discern differences between oxide growth and inner oxide layer morphology between the three practices. Switching from air to oxyfuel practice at a single temperature had the same increasing effect on the scale formation amount as a 25 °C temperature increase in air atmosphere. Inner oxide layer depth profiling revealed C, Si and Ni to be the main elements that differed between temperatures and atmospheres. A morphology study showed Si and Ni behaviour to be linked to breakaway oxidation.

scholarly journals X-ray Diffraction Investigation of Stainless Steel—Nitrogen Thin Films Deposited Using Reactive Sputter Deposition

Coatings ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 984
Author(s):  
Faisal I. Alresheedi ◽  
James E. Krzanowski
Keyword(s):  
Thin Films ◽  
Stainless Steel ◽  
Substrate Temperature ◽  
Peak Shift ◽  
304 Stainless Steel ◽  
Tetragonal Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Area Detector ◽  
Calculated Parameter

An X-ray diffraction investigation was carried out on nitrogen-containing 304 stainless steel thin films deposited by reactive rf magnetron sputtering over a range of substrate temperature and bias levels. The resulting films contained between ~28 and 32 at.% nitrogen. X-ray analysis was carried out using both the standard Bragg-Brentano method as well as area-detector diffractometry analysis. The extent of the diffraction anomaly ((002) peak shift) was determined using a calculated parameter, denoted RB, which is based on the (111) and (002) peak positions. The normal value for RB for FCC-based structures is 0.75 but increases as the (002) peak is anomalously displaced closer to the (111) peak. In this study, the RB values for the deposited films were found to increase with substrate bias but decrease with substrate temperature (but still always >0.75). Using area detector diffractometry, we were able to measure d111/d002 values for similarly oriented grains within the films, and using these values calculate c/a ratios based on a tetragonal-structure model. These results allowed prediction of the (002)/(200) peak split for tetragonal structures. Despite predicting a reasonably accessible split (~0.6°–2.9°–2θ), no peak splitting observed, negating the tetragonal-structure hypothesis. Based on the effects of film bias/temperature on RB values, a defect-based hypothesis is more viable as an explanation for the diffraction anomaly.

Magnetic Properties and Structural Transformation in Copper-304 Stainless Steel Multilayer Materials

1995 ◽  
Vol 382 ◽  
Author(s):  
K. Parvin ◽  
S.P. Weathersby ◽  
T.W. Barbee ◽  
T.P. Weihs ◽  
M.A. Wall
Keyword(s):  
Stainless Steel ◽  
Magnetic Moment ◽  
Magnetic Moments ◽  
High Volume ◽  
304 Stainless Steel ◽  
X Ray Diffraction ◽  
Multilayer Foils ◽  
Large Period ◽  
Fcc Phase ◽  
Bcc Phase

ABSTRACTMultilayer foils of Cu-304 stainless steel (304SS) with equal layer thicknesses in the range t=5.0-500 Å and total thicknesses 10-20 μm have been synthesized using magnetron sputtering at ambient substrate temperature. The x-ray diffraction data of as-deposited films show two structural regimes: small thickness (t=5-10 Å) which is characterized by epitaxial FCC growth of 304SS on copper, and large thickness (t=13.5-500 Å) which shows epitaxial FCC 304SS growth near the interface and BCC 304SS growth away from the interface. FCC structured films show very small magnetic moments at room temperature similar to bulk 304SS stable FCC phase. However, a strong magnetic moment is observed for thicker samples due to ferromagnetic metastable 304SS BCC phase. Two opposing transformations occur in the 304 layers as the samples are heated. The first transformation is from the metastable BCC 304SS to the stable FCC phase. This transformation produces a strong drop in magnetic moment and is clearly visible in the large period multilayers which contain high volume fractions of BCC 304SS. The second transformation is from the original FCC phase to a new stable BCC phase in the 304SS near the copper-304SS interfaces.The transformation is produced by diffusion of nickel from the 304SS into the surroundingcopper and the chemical destabilization of the FCC phase which starts near 400 ºC.This transformation produces a sharp increase in magnetic moment. The magnetic signal drops to zero near 675 ºC which is the Curie temperature of ferromagnetic BCC Fe.75 Cr25..

Wear and Friction of Nitrogen Ion Implanted Steel

1983 ◽  
Vol 105 (2) ◽  
pp. 239-244 ◽  
Author(s):  
J. A. Kirk ◽  
G. W. Egerton ◽  
B. D. Sartwell
Keyword(s):  
Stainless Steel ◽  
Ion Implantation ◽  
Wear Behavior ◽  
304 Stainless Steel ◽  
Nitrogen Ion Implantation ◽  
Wide Range ◽  
Wear And Friction ◽  
Nitrogen Ion ◽  
Contact Pressures ◽  
Ion Implanted

A pin on disk wear test apparatus was used to evaluate wear and friction properties for nitrogen ion implanted and non-ion implanted steel disks in the presence of a lubricant. Both AISI/1018 mild steel and 304 stainless steel were examined. Typical fluence levels for ion implantation were above 1017 ions/cm2. In this paper disk wear is measured directly by a Talysurf profilometer tracing of the disk wear scar. By varying the contact area of the pin it was possible to evaluate wear behavior of both unimplanted and implanted disks over a wide range of contact pressures. It is shown that stainless steel disk wear can be decreased by nitrogen ion implantation, provided that contact pressures remain less than the yield strength of the substrate material. No significant wear improvements were observed for 1018 steel. To evaluate improvements in hardness due to nitrogen ion implantation, very low penetration depth microhardness measurements were made and the indentation diagonals were measured in a scanning electron microscope. These results and their limitations are also presented.

The Effect of Nitrogen Implantation on Martensite in 304 Stainless Steel

1981 ◽  
Vol 7 ◽  
Author(s):  
R. G. Vardiman ◽  
R. N. Bolster ◽  
I. L. Singer
Keyword(s):  
Stainless Steel ◽  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
304 Stainless Steel ◽  
Nitrogen Implantation ◽  
Nitrogen Ion Implantation ◽  
Surface Polishing ◽  
Transmission Electron ◽  
Fine Surface ◽  
Nitrogen Ion

ABSTRACTMartensite will form in austenitic 304 stainless steel when it is deformed. Transmission electron microscope studies show that nitrogen ion implantation causes a reversion of the martensite to austenite. Specimens containing martensite resulting from fine surface polishing and heavy rolling are examined. The transformation is shown not to occur because of temperature increases during implantation. The effect is related to recent wear results in 304 stainless steel.

The Effects of Low-Energy-Nitrogen-Ion Implantation on the Tribological and Microstructural Characteristics of AISI 304 Stainless Steel

1994 ◽  
Vol 116 (4) ◽  
pp. 870-876 ◽  
Author(s):  
R. Wei ◽  
B. Shogrin ◽  
P. J. Wilbur ◽  
O. Ozturk ◽  
D. L. Williamson ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Elevated Temperatures ◽  
Wear Behavior ◽  
Plasma Nitriding ◽  
Low Energy ◽  
304 Stainless Steel ◽  
High Dose ◽  
Ion Energy ◽  
Wear Resistant ◽  
Nitrogen Ion

The effects of nitrogen implantation conditions (ion energy, dose rate, and processing time) on the thickness and wear behavior of N-rich layers produced on 304 stainless-steel surfaces are examined. Surfaces implanted at elevated temperatures (≈400°C) with 0.4 to 2 keV nitrogen ions at high dose rates (1.5 to 3.8 mA/cm2) are compared to surfaces implanted at higher energies (30 to 60 keV) and lower current densities (0.1 to 0.25 mA/cm2). The most wear-resistant surfaces are observed when the implanted-ion energy is near 1 keV and the dose is very large (> 2 × 1019 ions/cm2). Typically, surfaces implanted under these optimum conditions exhibit load-bearing capabilities at least 1000 times that of the untreated material. Some comparisons are also made to surfaces processed using conventional plasma-nitriding. Samples treated using either process have wear-resistant surface layers in which the nitrogen is in solid solution in the fcc phase. It is argued that the deep N migration (> 1 μm) that occurs under low-energy implantation conditions is due to thermal diffusion that is enhanced by a mechanism other than radiation-induced vacancy production.

scholarly journals Effect of Friction Pressure on Microstructure and Properties of Friction Welded Joints of Pure Aluminum/304 Stainless Steel

2021 ◽  
Author(s):  
Lizhe ZHAO ◽  
Wenbiao GONG ◽  
Rui ZHU ◽  
Mingyue GONG ◽  
Heng CUI
Keyword(s):  
Stainless Steel ◽  
Friction Welding ◽  
Pure Aluminum ◽  
Hardness Test ◽  
304 Stainless Steel ◽  
Joint Surface ◽  
X Ray Diffraction ◽  
Metallurgical Bonding ◽  
Friction Pressure ◽  
Mechanical Bonding

Continuous drive friction welding was used to realize the high quality connection between pure aluminum and 304 stainless steel. The composition of interface micro-zone and mechanical properties of joint were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), tensile test and hardness test. The formation mechanism of intermetallic compound (IMC) during friction welding was discussed. The results show that under the experimental parameters, the joint surface is uneven and two intermetallic compounds, Fe2Al5 and FeAl3, are formed. With the increase of friction pressure, the mechanical bonding degree of the joint decreases, the metallurgical bonding degree increases, the element diffusion distance increases from 1.4 to 1.9 um, the tensile strength of the joint can reach or even higher than that of the base metal on the aluminum side, and the maximum hardness increased from 414 HV to 447 HV.

Photocathode Protection Properties of TiO2/V2O5 Coating

2009 ◽  
Vol 79-82 ◽  
pp. 651-654 ◽  
Author(s):  
Min Jie Zhou ◽  
Li Zhong
Keyword(s):  
Stainless Steel ◽  
Steel Substrate ◽  
Sol Gel ◽  
304 Stainless Steel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Illumination ◽  
Type 304 ◽  
Type 304 Stainless Steel ◽  
Cathode Protection

Nano-sized TiO2/V2O5 bilayer coatings were prepared on type304 stainless steel substrate by sol-gel method and were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD). The performance of photocathode protection of the coating was investigated by the electrochemical method. SEM results indicate that the coating surface is continuous, uniform and dense, XRD spectra show that the coating is of anatase TiO2 and V2O5. The experimental results demonstrate that type 304 stainless steel with the bilayer coating can maintain cathode protection for 6h in the dark after irradiation by UV illumination for 1 h.

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