Skip to main content

Development of Rare Earth Surface Engineering Thermochemical Treatments

Objective


In the light of the progress made during the first two years, it was agreed at the Mid-Term Review to refocus the technical thrust of the Project during the second two-year period, putting experimental emphasis on the active screen plasma nitriding (ASPN) and plasma immersion ion implantation processes. It became clear early during the second two-year period of the project that reproducible RE-additions could not be developed for the plasma thermochemical processing methods employed here. This rendered some of the deliverables futile and necessitated modification of the original work plan in line with the decisions made at the Mid-Term Review. Since it became clear that it would be impossible to generate statistically useful data about the mechanical (fracture, tribological and contact fatigue) properties of RE-nitrided components or to develop software packages to predict machine element performance or residual stress development. These tasks were therefore cancelled and their loss was compensated for with an additional task, which was an extended plasma species study. The investigations into ASPN processing were also extended to incorporate properties evaluation of steel specimens nitrided with and without RE-additions, thus linking more directly with BRRT-CT98-5082 - New Efficient Steel Technologies (NEST).
Objectives and content
Surface engineering has been shown over the past two
decades to be the most technical and cost effective way
of improving the surface properties of materials and thus
combat surface degradation problems. The most important
recent development in rare earth technology has been in
the field of surface engineering, in particular,
thermochemical treatments by Chinese scientists, which
has only recently come to the attention of western
scientists.
The overall objective of the proposed research program is
to investigate the influence of rare earth additions on
the kinetics and properties of various plasma
thermochemical processes currently widely used in
industry, with the aims of improving efficiency, quality
and productivity, as well as reducing energy consumption.
Accordingly, the project seeks to adapt existing
technology for improved competitive leverage.
The thermochemical processes to be investigated are the
plasma nitriding and nitrocarburising surface engineering
technologies. The specific objectives of the proposed
program are:
to develop gaseous and vapour techniques for
incorporating rare earths via the wholly environmentally
friendly plasma thermochemical route;
to investigate the influence of rare earth additions on
the kinetics of layer growth, in the catalytic effect of
rare earths, with a view to obtaining up to a 50%
reduction in processing time for a specific case depth;
to investigate the alloying effects of rare earths and
to evaluate the processing of the alloyed layers with a
view to improving, for example, rolling contact fatigue
resistance by 20%;
to produce software packages for the predictive
performance of machine elements, such as bearings and
gears, after rare earth treatment.

Funding Scheme

CSC - Cost-sharing contracts

Coordinator

UNIVERSITY OF BIRMINGHAM
Address
Elms Road, Edgbaston
B15 2TT Birmingham
United Kingdom

Participants (4)

ATELIERS NIC GEORGES, SUCC ATELIERS GEORGES SARL ET CIE C.E.C.S
Luxembourg
Address
194,Route De Thionville 194
1817 Luxembourg
NITRUVID SNC
France
Address
9,Rue Jean Poulmarch 9 Zi Du Val
95100 Argenteuil
NSK-RHP European Technology Company Ltd
United Kingdom
Address
Mere Way Ruddington
NG11 6JZ Nottingham
Technische Universität Clausthal
Germany
Address
6,Agricolastraße
38678 Clausthal - Zellerfeld