§ Mr. Dalyellasked the Minister of Technology what study he has made of duplication of research effort into problems of metal fatigue and stress at the Building Research Establishment, the Royal Aircraft Establishment at Farnboroubh, and the Welding Research Association.
Mr. BenuThe following programmes of work on metal fatigue and stress are being carried out at these three organisations and two others, and I am satisfied they cover different areas.
Royal Aircraft Establishment
The programmes of work on fatigue and behaviour of metals under stress at the Royal Aircraft Establishment are orientatel towards metals and structures associated with aircraft engineering. The main effort is devoted to high strength aluminium alloys used in aircraft construction and no work is carried out on welded components. The programmes are mainly concerned with fundamental 264W aspects of fatigue damage, crack initiation and propagation, effects of aerodynamic heating on fatigue life, studies of cumulative damage under random loading conditions and accoustic fatigue.
British Welding Research Association
The relevant work at the British Welding Research Association is mainly concerned with brittle fracture and the fatigue behaviour of welded steel components of interest to general engineering. Programmes of work include Ministry earmarked grants on brittle fracture and fatigue under variable amplitude loading. Other items include work on electroslag welds, welded high strength steels, methods of improving the fatigue strength of welded joints and examination of the significance of defects in welds. Some effort is also devoted, under Government sponsorship, to the determination of the fatigue properties of welds in aluminium, titanium and nickel alloys for Defence interests.
Building Research Station
Research on metal fatigue at the Building Research Station is concerned with the problems of composite behaviour between constructional steels and concrete in bridge deck systems and in reinforced and prestressed concrete construction. The Building Research Station has established contact with the Royal Aircraft Establishment and the British Welding Research Association to ensure that there is an exchange of appropriate experience.
Other Ministry Stations
National Engineering Laboratory
The National Engineering Laboratory is carrying out an extensive programme of research on fatigue of metals to provide information which will improve the design of engineering components and also provide ideas which could lead to the development of materials and components of high fatigue resistance. Although the National Engineering Laboratory is carrying out no work on structures of the type undertaken in the three organisations mentioned above, the results of its researches are relevant to the avoidance of fatigue failure in the design of structures. All three organisations mentioned above are formally contacted by the National Engineering Laboratory each year when drawing up its research programme.
265WNational Physical Laboratory
The National Physical Laboratory is investigating methods of modifying the structure of low carbon steels to give improved strength and ductility combined with a study of the fundamental factors governing resistance to brittle fracture. The role of microstructural features in governing the fatigue strength of high strength steels is also being investigated.