PTFE/Al/MnO_2复合材料制备及性能

Preparation and Performance of PTFE/Al/MnO_2 Composite

采用模压烧结法制备聚四氟乙烯(PTFE)/Al/MnO_2复合材料。对不同配比的PTFE/Al/MnO_2试件,利用电子万能试验机测试其准静态压缩力学特性,利用高速摄影机和落锤仪测试其撞击感度,并获得试件特性落高H50。结果显示,PTFE/Al/MnO_2试件的压缩强度随PTFE体积分数的增加而增大,PTFE含量为70%时达到最大,最大真实应力为92MPa;不同PTFE含量会导致撞击发火现象产生明显差异,PTFE含量低于55%的试件在撞击发火过程中有明显二段反应现象,而PTFE含量高于60%的试件未发现二段反应;撞击感度随试件中PTFE含量的增加而减小,PTFE体积分数为40%的试件其特性落高为48cm,PTFE体积分数为70%的试件其特性落高为65cm。

PTFE/Al/MnO2 composite was prepared by molding and sintering method.The quasi-static compression feature of PTFE/Al/MnO2 material molded in different proportioning was tested by universal testing machine,and the impact sensitivity was tested by drop hammer machine and high-speed photography instrument was used to get the characteristic fall height H50.The results show that the strength of PTFE/Al/MnO2 specimens increases with the volume fraction of PTFE.Specimens with 70%PTFE have the highest strength and the maximum real stress is 92 MPa.The differences of PTFE content will lead to significant discrepancies in reaction phenomena.The specimens,in which the PTFE volume fraction is below 55%,will show an obvious twostage-reaction phenomenon under the impact ignition conditions.In contrast,the two-stage-reaction phenomenon disappears under the condition that the PTFE volume fraction is over 60%.Impact sensitivity goes down with the increase of PTFE volume fraction.The characteristic drop height H50 of specimens with 40%PTFE is 48 cm,while the H50 of specimens with 70%PTFE is 65 cm.