Abstract: The effect of Ti on the wettability in diamond/Al-Ti system was firstly studied in this paper;then, taking Al-Ti with different Ti content as matrix , adding Ti with different content and diamond , the bits without and with diamond were fabricated by a vacuum hot pressing equipment .The flexural strength of bits was measured and the holding force of Al-matrix bonded to diamond was calculated .The results show that with the increasing Ti content , the wettability between Al-Ti alloy and diamond is obviously improved.When the content of Ti is 5wt;, the combined state between Al-Ti alloy and diamond is the best , so the flexural strength values of the bits without and with diamond are both the highest and they are 135 MPa and 102 .1 MPa respectively;moreover , the holding force coefficient is also the largest and the value is up to 75 .6;.

Key words: The effect of Ti on the wettability in diamond/Al-Ti system was firstly studied in this paper;then, taking Al-Ti with different Ti content as matrix , adding Ti with different content and diamond , the bits without and with diamond were fabricated by a vacuum hot pressing equipment .The flexural strength of bits was measured and the holding force of Al-matrix bonded to diamond was calculated .The results show that with the increasing Ti content , the wettability between Al-Ti alloy and diamond is obviously improved.When the content of Ti is 5wt;, the combined state between Al-Ti alloy and diamond is the best , so the flexural strength values of the bits without and with diamond are both the highest and they are 135 MPa and 102 .1 MPa respectively;moreover , the holding force coefficient is also the largest and the value is up to 75 .6;.