Innovative Forging and Fabrication Solutions for the Energy Sector

Lead Research Organisation: University of Sheffield
Department Name: Materials Science and Engineering

Abstract

The contribution from the University of Sheffield to the "Innovative Forging and Fabrication Solutions for the Nuclear
Industry" project will be on the modelling and its validation of the welding process and development and property validation
of post weld heat treatment schedules using the heat treatment simulator produced in EP/L50466X/1. This will be
undertaken by Prof Wynne, Dr Palmiere, and Dr Jackson in collaboration with a PhD Student, supported by the grant. Thus
the aim of the project in its broadest sense is: Development of quality heat treatment schedules for thick sectioned welds.
This will be achieved by the following four work packages.
Work Package 1: Validate Finite Element Model of Thick Section Welds produced using Reduced Pressure Electron Beam
Welding (Phd Student, UoS, TWI, SFIL)
This includes determination of temperature distribution during welding, size of weld zone, size of heat affected zone,
cooling rates, and residual stress distribution. Furthermore, material type sensitivity will be investigated from current
nuclear grade steels through to next generation materials.
Work Package 2: Microstructure Evaluation of As-Welded Microstructure. (PhD Student, UoS)
A detailed investigation of the as-welded microstructure in terms of alloy segregation, weld zone sizes, grain size,
transformation product, etc will be undertaken using optical and electron microscopy. Results will be compared to the modelling results produced in WP1
Work Package 3: Development of Potential Heat Treatment Schedules for As-Welded Materials. (PhD Student, UoS, SFIL)
Review of literature on potential heat treatment schedules for welded materials, concentrating on issues relating to the
general physical metallurgy, welding methodologies and metallurgical challenges, as well as NDT evaluation techniques.
The project has already identified the steel compositions, and so this particular task should be highly focused, identifying
material and post-production issues. Thermodynamic modelling of the steel compositions will indicate the phases and
phase fractions expected. Initial risks associated with the use of the steel compositions will also be assessed.
Work Package 4: Application of Identified Heat Treatment Schedules in the Heat Treatment Simulator. (PhD Student, UoS,
SFIL)
Following on from the outcomes of WP3, the chosen heat treatment schedules will be undertaken on as welded material
using the heat treatment simulator. Mechanical property evaluation will be in the form of tensile tests, Charpy impact tests,
crack tip opening displacement tests, and hardness profiles. Microstructure characterisation will produce information on
phase fractions, segregation profiles, and microstructure type and uniformity using optical and scanning electron
microscopy. These results will then form the basis for large scale trials.
Work Package 5: Validate Linkage Between Chosen Heat Treatment and Actual Component. (PhD Student, UoS, SFIL)
This work package will compare and contrast simulated results, both mechanical and microstructure, with an actual
component. Extreme areas of the as-forged component will be investigated to ensure good variability coverage.
Microstructure at levels above optical, i.e. precipitation density, will be taken thus requiring advanced characterisation
methods such as scanning and transmission electron microscopy.

Planned Impact

This project has much potential impact for a number of sectors including the metals manufacturing industry, society, and
the nuclear power manufacturing industry.
Metals Manufacturing Industry: The major industrial beneficiary of this research will be Sheffield Forgemasters International
Limited, a UK company at the forefront of manufacture of large scale castings and forgings. They will be able to rapidly
validate numerical models of their process route, leading to enhanced productivity. As a consequence, all their customers
will have enhanced products at reduced costs, due to significant reductions in lead times. They will also gain greater levels
of confidence in incorporating non-standard steel grades with enhanced properties into new components with very thick
sections, leading to greater customer satisfaction and the potential for a greater share of a large global market.
Society: The greater competitiveness and improved efficiencies generated by this project will help maintain the UK's
leading role in the manufacture of large scale steel castings and forgings, leading to enhanced employment opportunities
and reduction in green house gases.
Nuclear Power Manufacturing Industry: Components of greater size will be able to be manufactured with lower risk due to
an optimised and validated combined forging, forming, and welding lean manufacturing technique, establishing a unique
low cost manufacturing route in the nuclear supply chain, breaking down barriers to market entry for the UK civil nuclear
supply as a whole.

Publications


10 25 50
 
Description business development for Sheffield Forgemasters
First Year Of Impact 2014
Sector Energy
Impact Types Economic