CoA. Memos: Materials (1963-1966)
Permanent URI for this collection
Browse
Recent Submissions
Item Open Access High temperature creep properties of W-ThO2 alloy(College of Aeronautics, 1966-03) Clifton, T. E.; Cook, P.Introduction This memorandum reports a series of experiments to determine some tensile creep properties of W.Th02 alloy at elevated temperatures.Item Open Access High temperature creep properties of Mo T.Z.M. alloy(College of Aeronautics, 1965-10) Clifton, T. E.; Cook, P.Introduction This memorandum reports a series of experiments to determine some tensile creep properties of Mo T.Z.M. alloy at elevated temperatures in the range 1200°C to 1800°C, the material being in sheet form. A subsequent memorandum will report some creep properties of W-Th02 alloy.Item Open Access Room temperature torsional fatigue properties of an iridium: 5% tungsten alloy(College of Aeronautics, 1965-02) Younger, A.; Whitbread, R. C.Introduction Fine wires of an iridium-5% tungsten alloy have been developed as a potential material for use in springs operating at high temperatures. Their suitability for such applications will to a considerable extent depend on satisfactory fatigue properties. The Materials Department of The College of Aeronautics was approached with a view to determining these torsional fatigue properties. This report covers preliminary work into this problem, namely the torsional fatigue behaviour of 0.020 ins. diameter wires at room temperature.Item Open Access Push-pull fatigue properties of wires in an iridium: 5% tungsten alloy(College of Aeronautics, 1965-02) Younger, A.; Whitbread, R. C.Introduction. The Materials Department at Cranfield was approached by the Platinum Metals Division of the International Nickel Co. with a view to carrying out a preliminary survey of the fatigue properties of an iridium-5% tungsten alloy. This alloy in drawn wire form is intended for future use in springs subjected to elevated temperatures. For this reason it was decided to investigate both the tensile and the torsional fatigue properties of these wires at room and elevated temperature. This report covers the tensile room temperature properties; subsequent reports will deal with the torsional and the high temperature properties.Item Open Access Experimental techniques used in the high temperature heat-treatment of some tungsten-thoria alloys(College of Aeronautics, 1964-12) Younger, A.The high temperature apparatus developed in the Department of Materials for the torsional creep testing of graphite at temperatures up to 3000 oC has been utilised to heat-treat tungsten-thoria alloys at temperatures up to 2500 oC. Modifications to the torsional loading system have enabled some of these heat-treatments to be carried out under an applied stress.Item Open Access Assessment of blasted surfaces progress report no. 3(College of Aeronautics, 1964-09) Apps, R. L.Introduction This report covers work carried out from January - August, 1964. The work has largely consisted of further tests with the Cranfield reflectivity equipment and associated measurements of pull-off strength, but a brief assessment has also been made of an instrument for measuring reflectivity developed by the Paint Research Station. A number of miscellaneous tests are also reported. The final months of the period covered by the report have been spent in the design and construction of a new reflectivity instrument which incorporates features that the previous instruments have shown to be desirable'. Particular topics reported cover the effect of grit size and blasting time, and also a determination of the effect of using light sources of specific colours instead of white light. Much of this work has been done at laboratories and works away from Cranfield to allow external assessment of the reflectivity equipment. A number of miscellaneous tests have also been made covering the use of non-metallic grits and 'Jasonl type hammers for surface preparation, the assessment of sprayed coatings by a simple bend test and the examination of the variation of strength with time of two adhesives to determine whether an adhesive could be used for practical site testing of sprayed coatings.Item Open Access The replica strain gauge technique(College of Aeronautics, 19) Castle, W.; Younger, A.; Sollars, A. R.Surface deterioration and dimensional stability tests have been carried out on the low melting point replication alloy described in the first report. A range of alloys for the replication of surfaces at temperatures in the range 120 - 150°C has been prepared and evaluated. Preliminary studies of a cold pressing technique using fully annealed commercial purity aluminium as the replication material have shown that the technique has considerable promise for application over a wide range of temperatures.Item Open Access The behaviour of the aluminium alloy RR58 under combined creep and fatigue conditions. Part 1, the hydraulic combined creep and fatigue machine(College of Aeronautics, 19) Younger, A.; Clifton, T. E.Item Open Access Assessment of blasted surfaces: progress report no. 2(College of Aeronautics, 1964-02) Pamdeth, N. M.; Apps, R. L.Introduction Previous work had shown that the conditions of grit blasting markedly affected the reflectivity of a mild steel surface and that measurement of reflectivity thus offered a method for the assessment of blasted surfaces. The increase in reflectivity of a series of blasted specimens was found to relate to decreasing surface quality and, after metal spraying, to decreasing bond strength between the base and the sprayed metal. However, one series of specimens did not show any correlation between reflectivity and surface quality and it was decided that an examination of a considerable number of specimens prepared under more carefully controlled conditions was necessary for the next stage of the work. The present report gives the results of reflectivity and bond strength measurements on some 300 specimens of mild steel blasted under a number of different conditions by three suppliers. Reflectivity measurements again showed 'that specimens prepared by any one supplier could be placed in a series of increasing reflectivity, although some difficulties were still encountered in relating the result of different suppliers. These difficulties were most marked with specimens blasted with worn grit. However, correlation between reflectivity, pull-off strength and blasting conditions was good with the series of specimens provided by two suppliers. The series from a third supplier has not been fully tested yet, but very little difference in reflectivity readings has been found.Item Open Access Characteristics of the high temperature mechanism of creep and recovery in graphite(College of Aeronautics, 1963-11) College of Aeronautics, (Cranfield)The research reported in this document has been made possible through the support and sponsorship of the U.S. Department of the Army, through its European Research Office. This report, not necessarily in final form, is intended only for the internal management use of the Contractor and the U.S. Department of the Army.Item Open Access Research project 1 of the metal spraying and coating Division of the Institute of Welding: progress report no. 1(College of Aeronautics, 1963-08) College of Aeronautics, (Cranfield)Introduction The quality of a sprayed metal deposit is known to be related to the nature of the prepared surface of the base metal. Grit blasting is a common method of surface preparation, and the actual profile or surface contour of the prepared surface can be varied considerably by variation in blasting conditions. The exact requirements of an acceptable surface have never been accurately stated, although a degree of undercut is. considered essential. The object of the present work is to develop a non-destructive method for the assessment of blasted mild steel surfaces in terms of suitability for metal spraying. Such a method needs to combine simplicity and speed, so that it can be used by normal inspection personnel without delaying production. Preferably the method should incorporate a 'failsafe! mechanism.. A number of possible assessment methods have been considered, but attention has been largely concentrated on measurement of the diffuse reflectivity of blasted surfaces. In reality, of course, this is simply an attempt to replace the eye in visual inspection with an instrument, and so remove the human element. Results have been reasonably encouraging, but it is obvious that many more samples need to be examined before a true judgement can be made. Some difficulty has been encountered in deciding the requirements for an acceptable surface. For this reason, a part of the experimental effort has been devoted to the examination of blasted surfaces, and to the measurement of bond strength after metal spraying. A brief review of literature has also been included.