摘要:
A method of fatigue testing a component comprising the steps of machining a channel of predetermined depth and predetermined width in a surface of a component, applying a salt solution into the channel in the surface of the component and heating the component to a suitable temperature to evaporate the solvent from the salt solution to deposit the salt in the channel in the surface of the component, placing the component in an atmosphere containing air and sulphur dioxide at a predetermined temperature for a predetermined period of time to precondition the grain boundaries, and fatigue testing the component. The method is useful for determining the fatigue life of gas turbine engine discs or gas turbine engine rotor blades particularly the firtree shaped disc posts or the firtree shaped rotor blade roots.
摘要:
The invention provides a fiber testing device for thermomechanical testing of fibers which preferably inludes a linear step motor (10) coupled to a first fiber gripping jaw (18). A second fiber gripping jaw (24) is positioned in linear relation to the first gripping jaw (18) and is coupled to a load cell (32). Advantageously, the apparatus includes a chamber (43) for maintaining a fiber test specimen (20) in a substantially thermally isolated environment during testing of the fiber. A heating means (62) and a cooling means (63) are connected to the chamber (43). The heating means (62) and cooling means (63) are controlled by a control means (70,72,80) which also controls the position of the linear step motor (10). The fiber testing device of the invention is capable of performing complicated mechanical and thermal fiber testing protocols without operator involvement except for initiation of the testing sequence.
摘要:
A method of fatigue testing a component comprising the steps of machining a channel of predetermined depth and predetermined width in a surface of a component, applying a salt solution into the channel in the surface of the component and heating the component to a suitable temperature to evaporate the solvent from the salt solution to deposit the salt in the channel in the surface of the component, placing the component in an atmosphere containing air and sulphur dioxide at a predetermined temperature for a predetermined period of time to precondition the grain boundaries, and fatigue testing the component. The method is useful for determining the fatigue life of gas turbine engine discs or gas turbine engine rotor blades particularly the firtree shaped disc posts or the firtree shaped rotor blade roots.
摘要:
Die Erfindung betrifft ein Verfahren zur Erfassung des Ist-Zustandes im Hinblick auf eine Alterung eines Behälters, insbesondere Composite-Druckgasbehälter für Fahrzeuge, der in bestimmten Zyklen mit einem unter Druck stehenden Gas befüllt und entleert und je nach Ist-Zustand einer wiederkehrenden amtlichen Bauteilprüfung unterzogen wird. Erfindungsgemäß ist vorgesehen, daß zum einen die Amplitude der Druckzyklen, d. h. die Höhe des Befülldruckes minus dem Restdruck vor dem nächsten Befüllvorgang als auch die Temperaturzyklen, d. h. die Max.- und Min.-Temperaturen innerhalb eines vorgegebenen Zyklus meßtechnisch erfaßt und mittels eines geeigneten Rechenprogrammes daraus die wahre mechanische Alterung des Behälters berechnet wird, wobei zusätzlich überkritische Dehnungen in Umfangs- und / oder Längsrichtung dieses Behälters erfaßt und bei der Berechnung der wahren mechanischen Alterung mitberücksichtigt werden.
摘要:
A method for determining an approximate value for a parameter characteristic of the fatigue state of a part as a result of a time-varying stress to which it is subjected by means of a number of load cycles should, itself, during comparatively lengthy stress cycles, enable a prognosis concerning the current fatigue state of the part, this prognosis being, in particular, adapted to the needs and suited for the real-time determination of maintenance intervals. To this end, in addition to optionally already fully completed load cycles, a first partially completed load cycle is also taken into consideration during the determination of the parameter, whereby temporary stress values for phases that have not yet been run through of the partially completed load cycle are, together with a predetermined fixed value, taken into consideration.
摘要:
A method and apparatus are described for quantative determination of the level of spalling of a protective surface coating as a result of repetitive heating and cooling. The method comprises introducing at least one radionuclide into the protective coating of an article (16), alternately heating and cooling the article (16) for a predetermined number of heating and cooling cycles, collecting the spalled particles (10) and measuring the radioactivity thereof. The apparatus comprises a chamber (2) for receiving the coated article, means (4) for heating the chamber (2) or the article (16) and a spall collector (8). The spall collector (8) is characterized in having means for immobilizing any spalled coating particles (10) and in being so adapted that the level of radioactivity of any spalled particles can be measured by a η-spectrometer.
摘要:
A method for evaluating the life of a connection between members (1, 2, 3), comprising the steps of: extracting parameters defining the shearing strain (γ) of a predetermined model representing said connection thereby to calculate the values of plural shearing strains of said connection; calculating the equivalent strain amplitude (Δε eq ) corresponding to thermal fatigue stress for each of the values of said plural shearing strains; defining the relationship between said shearing strain and said equivalent strain amplitude; formulating a life evaluation criterion equation expressed using said equivalent strain amplitude; calculating, for said connection, the equivalent strain amplitude corresponding to each of the shearing strains actually measured using said equation; and substituting said equivalent strain amplitude for the life evaluation criterion equation to acquire the life of said connection. Further, in this method, an equation for evaluating the advancement of a crack (4) is made using said equivalent strain amplitude, and said equivalent is substituted for said crack advancement evaluation equation to calculate the length of the crack (4).
摘要:
A method for measuring a dynamic viscoelasticity of a particulate material uses, as a sample to be subjected to the dynamic viscoelasticity measurement, a sheet-shaped test piece in which the particulate material to be measured is attached to an adhesion layer formed on a heat-resistant sheet base material. With regard to the measurement conditions of the dynamic viscoelasticity measurement, the measurement temperature is within a predetermined temperature range of from -150 to 300°C, the heating rate is a constant rate ranging from 0.01 to 100 °C/minute, the measurement frequency is a constant frequency ranging from 0.01 to 100 Hz, and a sine wave control tensile mode is employed. When the particulate material is attached to the adhesion layer, the particulate material crushed in advance is sprinkled on one side of the adhesion layer and then the particulate material-sprinkled surface is squeegeed and/or air-blown.