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.

Host Phases for Actinide Elements in the Metallic Waste Form

2002 ◽  
Vol 757 ◽  
Author(s):  
D. E. Janney
Keyword(s):  
Stainless Steel ◽  
Electron Microscope ◽  
Electron Diffraction ◽  
Transmission Electron Microscope ◽  
Waste Form ◽  
Dissolution Behavior ◽  
Release Rates ◽  
Waste Forms ◽  
Transmission Electron ◽  
Simulated Waste

ABSTRACTArgonne National Laboratory has developed an electrometallurgical process for conditioning spent sodium-bonded metallic reactor fuel prior to disposal. A waste stream from this process consists of stainless steel cladding hulls that contain undissolved metal fission products such as Tc, Ru, Rh, Pd, and Ag; a small amount of undissolved actinides (U, Np, Pu) also remains with the hulls. These wastes will be immobilized in a waste form whose baseline composition is stainless steel alloyed with 15 wt% Zr (SS-15Zr). Scanning electron microscope (SEM) observations of simulated metal waste forms (SS-15Zr with up to 11 wt% actinides) show eutectic intergrowths of Fe-Zr-Cr-Ni intermetallic phases with steels. The actinide elements are almost entirely in the intermetallics, where they occur in concentrations ranging from 1–20 at%. Neutron- and electron-diffraction studies of the simulated waste forms show materials with structures similar to those of Fe2Zr and Fe23Zr6.Dissolution experiments on simulated waste forms show that normalized release rates of U, Np, and Pu differ from each other and from release rates of other elements in the sample, and that release rates for U exceed those for any other element (including Fe). This paper uses transmission electron microscope (TEM) observations and results from energy-dispersive X-ray spectroscopy (EDX) and selected-area electron-diffraction (SAED) to characterize relationships between structural and chemical data and understand possible reasons for the observed dissolution behavior.Transmission electron microscope observations of simulated waste form samples with compositions SS-15Zr-2Np, SS-15Zr-5U, SS-15Zr-11U-0.6Rh-0.3Tc-0.2Pd, and SS-15Zr-10Pu suggest that the major actinide-bearing phase in all of the samples has a structure similar to that of the C15 (cubic, MgCu2-type) polymorph of Fe2Zr, and that materials with this structure exhibit significant variability in chemical compositions. Material whose structure is similar to that of the C36 (dihexagonal, MgNi2-type) polymorph of Fe2Zr was also observed, and it exhibits less chemical variability than that displayed by material with the C15 structure. The TEM data also demonstrate a range of actinide concentrations in materials with the Fe23Zr6 (cubic, Mn23Th6-type) structure.Microstructures similar to those produced during experimental deformation of Fe-10 at% Zr alloys were observed in intermetallic materials in all of the simulated waste form samples. Stacking faults and associated dislocations are common in samples with U, but rarely observed in those with Np and Pu, while twins occurred in all samples. The observed differences in dissolution behavior between samples with different actinides may be related to increased defect-assisted dissolution in samples with U.

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.

Effect of metal surfaces on matrix-assisted laser desorption/ionization analyte peak intensities

2017 ◽  
Vol 23 (5) ◽  
pp. 287-299 ◽  
Author(s):  
Vidhyullatha Kancharla ◽  
Sajid Bashir ◽  
Jingbo L Liu ◽  
Oscar M Ramirez ◽  
Peter J Derrick ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Thermal Properties ◽  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Laser Desorption ◽  
Laser Desorption Ionization ◽  
Desorption Ionization ◽  
Transmission Electron ◽  
Matrix Assisted Laser ◽  
Matrix Assisted Laser Desorption

Different metal surfaces in the form of transmission electron microscope grids were examined as support surfaces in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry with a view towards enhancement of peptide signal intensity. The observed enhancement between 5-fold and 20-fold relative to the normal stainless steel slide was investigated by applying the thermal desorption model for matrix-assisted laser desorption/ionization. A simple model evaluates the impact that the thermal properties of the metals have on the ion yield of the analyte. It was observed that there was not a direct, or strong, correlation between the thermal properties of the metals and the corresponding ion yield of the peptides. The effects of both fixed and variable laser irradiances versus ion yield were also examined for the respective metals studied. In all cases the use of transmission electron microscope grids required much lower laser irradiances in order to generate similar peak intensities as those observed with a stainless steel surface.

Metastable Phase Formation in the Ti-rich end of the Ti-(Co,Ni) System

1989 ◽  
Vol 157 ◽  
Author(s):  
David A Lilienfeld ◽  
Peter Bergesen
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Composition Range ◽  
Metastable Phase ◽  
Ternary Alloys ◽  
Stable Phase ◽  
Transmission Electron ◽  
Metastable Phase Formation ◽  
Nitrogen Ion ◽  
Fcc Phase

ABSTRACTThe Ti-rich end of the Ti-(Co,Ni) was investigated by ion mixing. A metastable FCC phase was discovered which formed over a broad composition range. The stable phase was formed by ion mixing at 350°C in some samples but was not formed until 550°C during in situ heating in the Transmission electron microscope. Some of the Ni-rich ternary alloys did not amorphize even after liquid nitrogen ion irradiations. This result indicates that the amorphization mechanism for the TiNi CsCl phase is different from that of the TiCo CsCl phase.

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