杨木/刺槐复合结构胶合性能的压痕表征

以杨木、刺槐及异氰酸酯胶黏剂(EPI)制成胶合构件,进行了胶层剪切强度的测试及在宏观范围内胶合性能的压痕表征。结果表明:刺槐间、杨木间的胶层剪切强度分别为7.9、6.2 MPa,杨木与刺槐间胶层剪切强度为5.4～5.7 MPa。460 N荷载条件下,1.6 MPa和1.0 MPa胶合压力制备的杨木与刺槐间胶层部位压痕蠕变分别为21.31%和25.37%,杨木间和刺槐间的压痕蠕变差异不显著。杨木/刺槐间胶层部位的塑性变形功与压痕功比值介于杨木间和刺槐间的值,EPI胶层对杨木抗塑性变形有贡献但对刺槐的作用不明显。杨木与刺槐间胶层部位的名义硬度比杨木与杨木间大,比刺槐与刺槐间小。

Shear strength on adhesive layer and indentation characterization of poplar/black locust composite structure

The shear strength and macro indentation characterization on bonding parts of gluing specimen that made from poplar, black locust and emulsion polymer-isocyanate adhesive(EPI)were tested and characterized. The results showed that shear strength of black locust composite and poplar composite were 7.9 MPa and 6.2 MPa respectively, and the shear strength range of black locust/poplar composite was from 5.4 to 5.7 MPa. The indentation creep at test force 460 N on the bonding parts of poplar/black locust composite made under bonding pressures 1.6 MPa and 1.0 MPa were 21.31% and 25.37%, respectively, and there was no significant difference between black locust composite and poplar composite. The ratio of plastic deformation indentation work to total indentation work on the bonding parts of poplar/black locus composite was in the range of which on the bonding parts of poplar composite and black locus composite, the EPI adhesive layer contributed to the plastic deformation resistance of poplar and not to black locus. The normal hardness of the bonding part of poplar/black locus composite was higher than poplar and poplar composite, while lower than black and black locus composite.