| The residual gases in vacuum chambers of high energy particle accelerators will lead to beam loss and therefore ultra-high vacuum should be maintained to ensure desirable beam life. The storage ring of accelerator is usually pumped by vacuum pumps such as sputtering ion pumps and titanium sublimation pumps scattered along the vacuum chambers. The vacuum chambers are usually long and thin pipes with low vacuum conductance, so the outgassing from the inner wall, induced by the bombardment of synchrotron light and particles with high energy, will result in the longitudinal gradient of pressure along the chambers.Domestic researches on coating the non-evaporable getter film onto the vacuum chamber of particle accelerator have only been carried out recently and rarely reported. Because of the unique vacuum performance and good prospect of application in particle accelerator, studies on preparation and characterization of TiZrV getter film were carried out in our laboratory. The summary of this work is demonstrated as follows.Considereing the feature of coating on the inner wall of a long pipe, a direct-current magnetron sputtering facility was designed and constructed. The discharge characteristic of the facility was studied and desirable TiZrV film could be obtained by adjusting the deposition parameters. The TiZrV samples were measured and analysed by Scanning Electron Microscopy, X-ray Photoelectron Spectroscopy and X-ray Diffraction. Besides those, vacuum-related characteristics including the second electron yield (SEY), photon stimulated desorption (PSD) and pumping performance were studied.For positron, proton and heavy ion accelerators, the electron cloud effect, which will reduce the beam quality and even disrupt the normal operation, tends to arise in the vacuum chamber with high SEY. Related studies abroad show that TiZrV film can be used to surpress the electron cloud because of its low SEY. The measurement of the SEY of TiZrV showed that the maximum as received was 2.03 and decreased to 1.55 after an in situ thermal treatment at 200°C for 2 hours. The value after heating is higher than that reported elsewhere and this may be due to the recontamination of the gas desorbed from the sample and the SST sample holder during heating and electron conditioning.To examine the effect of TiZrV film in reducing the PSD of a vacuum chamber, PSD measurement for a stainless steel chamber with and without TiZrV film were carried out in the PSD experiment station of the Machine Studying Beamline of Hefei Light Source. The results showed that the PSD yields of stainless steel and TiZrV for the residual gases were all of the order of 10-410-3initially, and reduced dramatically to the order of 10-510-4 and 10-610-5 respectively after being heated at 200°C for 24 hours.The pumping ability is an important criterion to evaluate the performance of getter. The test gases were CO and H2, which are usually the primary residual gases in untra-high vacuum. The TiZrV-coated pipe was heated on different temperatures and with different durations. The results showed that TiZrV had good pumping for CO and H2. The pumping speed and capacity for them after being heated at 200°C for 24 hours were 0.23 L·s-1·cm-2, 0.02 L·s-1·cm-2 and 6.8×10-5 Pa·L·cm-2, 6.6×10-2 Pa·L·cm-2 respectively. After the same heating treatment, the pumping speed for CO was one order of magtitude higher than that for H2, while two orders of magtitude lower as for the pumping capacity. The pumping performance of TiZrV is closely related to the heating process and can be enhanced by increasing the activation temperature and duration, which can be implemented in practice to restore the best pumping ability.The technology of coating TiZrV film onto the interior wall of vacuum chamber of particle accelerator by DC magnetron sputtering was mastered basically and some engeneering experience was acquired. Vacuum-related performances of TiZrV were systemically understood through this work.
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