Effect of inclusions modified by rare earth elements (Ce, La) on localized marine corrosion in Q460NH weathering steel

Influence of rare earth metals on mechanisms of localised corrosion induced by inclusions in Zr-Ti deoxidised low alloy steel

The connection between the cleanliness of 52100 type bearing steels and their reliability has been well documented. Most research over the past 30 years has focused on sensitive compositional control during metallurgical refinement, leading to steels so clean that industrial cleanness standards are no longer suitable for quantifying further improvements. There is less literature, however, detailing the mechanism by which different impurities initiate rolling contact fatigue (RCF). Early work focused on comparing fatigue lives with cleanness ratings, which include a worst field analysis to determine the inclusion content and post-failure analysis to determine damage nucleation sites. The stress concentrations around discontinuities in the steel matrix can now however be visualised using computational modelling techniques. There is now a much clearer picture of how non-metallic inclusions (NMIs) nucleate fatigue damage by causing changes in the subsurface microstructure, including white etching regi...

Improving the reliability of highly loaded rolling bearings: the effect of upstream processing on inclusions

A high strength, high fracture toughness steel alloy consisting essentially of, in weight percent, about ______________________________________ C 02-033Mn 020 maxSi 01 maxP 0008 maxS 0004 maxCr 2-4Ni 105-15Mo 075-175Co 8-17Ce Effective amount-0030La Effective amount-001Fe Balance______________________________________ and an article made therefrom are disclosed A small but effective amount of calcium can be present in this alloy in substitution for some or all of the cerium and lanthanum The alloy is an age-hardenable martensitic steel alloy which provides a unique combination of tensile strength and fracture toughness The alloy provides excellent mechanical properties when hardened by vacuum heat treatment with inert gas cooling and has a low ductile-to-brittle transition temperature

High strength, high fracture toughness alloy

https://onlinelibrary.wiley.com/doi/pdf/10.1002/srin.201970101

Characterization Transformation of Inclusions Using Rare Earth Ce Treatment on Al-Killed Titanium Alloyed Interstitial Free Steel

Rare earth (lanthanide metals) addiiions to continuously cast steel are particularly advantageous because of their ability to refine as-cast structures, reduce segregation and increase hot ductility at temperatures just below that of solidification. The complete shape control of sulfides in steels containing Rare Earth Metals (REM), whether continuously cast or ingot cast, is primarily responsible for improvements in ductility related mechanical properties, weldability, fatigue resistance and resistance to hydrogen damage. Complete sulfide shape control can be obtained with REM additions at sulfur levels as high as.020%. The greatest improvements, however, are obtained with REM additions to low sulfur steels. However, to achieve full operational advantages afforded by REM, nozzle blockage problems must be circumvented. Water model studies indicate a possible solution.

Rare Earth Additions in Continuously Cast Steel

This article describes the application of argon teeming techniques to degassed steel for the production of high-quality forgings.

William G. Wilson

Papers

Rare Earth Additions in Continuously Cast Steel

Argon Teeming of Degassed Steel