Asymmetric carbon fibre reinforced aluminum alloy laminates was manufactured for the purpose with repeat tensile test,
which will be applied in composite pressure vessel. Ultrasonic C scan and A scan approach are used to evaluate the
damage of the asymmetric CFRP-Al (carbon fibre reinforced aluminum alloy) laminates. Nondestructive detection is
carried out for the CFRP-Al laminates before and after tensile test. Comparison results and pulse echo analysis show that
when subjected to repeat tensile test with 70% elastic limit strain load of the CFRP laminates, the interface debonding
between CFRP and Al will not occur but the delamination within CFRP laminates becomes the main damage of the
asymmetric CFRP-Al laminates. This investigation indicated that combined ultrasonic C scan and A scan is available for
damage evaluation of fibre metal laminates.
Light-weight carbon fiber composite pressure vessel with inner thin-wall aluminum alloy liner has main problem of local buckling during manufacture and working process. The approach of acoustic emission and Bragg grating are adapted to monitoring the light-weight composite vessel under water pressure. Two channels of acoustic emission (AE) were bonded to front dome and cylinder to monitoring the performance of the vessel withstanding maximum 4.5MPa water pressure during loading, maintaining and unloading. Meantime six fiber Bragg sensors (FBG)were attached to front dome and cylinder of the outer surface by hoop and meridian direction respectively in order to monitor the vessel behavior. Analysis indicated Bragg sensors can evaluate outer surface behavior of the vessel with pressure. AE character parameters analysis illustrated the local buckling of inner thin-wall liner.
Composite pressure vessel with thin metal liner has the advantage of both composite and metal. Due to the difference of
elastic strain limits of composite and metal, there is problem of the compatibility of deformation. Nine fiber Bragg
gratings were bonded to the surface of longitudinal and hoop directions of pressure vessel to monitor the strain status
during 4.5MPa service pressure condition. The measured strain by the Bragg sensor is perfectly linear with the applied
force. However, the hoop strain decreased as loading process and increased as unloading process, it is also negative
value on middle part of the dome. The phenomena had been discussed in this investigation. As a smart structure Bragg
sensor can detect the real strain state of composite pressure vessel and is suitable for damage monitoring in service.
Analyzing result shows the pressure vessel can work safely with the applied hydrostatic pressure.
In this paper, a 3-D noncontact measuring method using single-line structural light is put forward. First, the light path for measuring is designed according to the principles, then the mathematical model is derived, in which necessary parameters are defined. Finally the implementation of the system is given out, and the experimental testing results as well.
In this paper, the 3-D measuring system based on structure-light, which principle is that its distortion can be transformed into the height change in the direction of the stripe if a single-stripe light is emitted and observed sideways and a generator emitting a single-stripe light and a camera can make up of a 3-D measuring system, was designed in order to inspect the shape of product surface on-line in the industrial production. At first, this paper introduces the structure of the 3-D measuring system using the single-stripe structured-light and its buildup. At second, its operating principle is introduces, its mathematical model is established and the calibrating method for it is put forward. At last, its prototype is produced and calibrated. The experimental result shows that the mathematical model put forward in this paper is suitable for engineering, the system calibration method suggested in this paper becomes more simple than other calibration methods, the system prototype has the range of 630mm(Depth)×400mm(Height) and the accurate of 0.3%(Depth)×0.5%(Height).