短切玄武岩纤维对磷石膏抗折强度影响研究

研究了掺加短切玄武岩纤维对磷石膏抗折强度的影响,分析了短切玄武岩纤维增强磷石膏的机理,通过SEM手段对玄武岩纤维-磷石膏界面进行了研究。结果表明,短切玄武岩纤维增强磷石膏效果明显,随着短切玄武岩纤维掺量的增加,增强效果趋于稳定,长度为6 mm短切玄武岩纤维比12 mm纤维效果更好。6 mm短切玄武岩纤维掺量为1.6%时增强效果趋于稳定,2 h和绝干抗折强度分别达到7.5 MPa和15.2MPa,相较空白组提高115%和85%。经过盐酸刻蚀处理后的6 mm短切玄武岩纤维增强效果更好,在最佳掺量1.4%时,原料遇水后2 h和绝干抗折强度分别达到8.3 MPa和17.0 MPa,较空白组提高137%和107%。短切玄武岩纤维磷石膏复合材料的破坏形式主要是基体断裂和纤维拔出,玄武岩纤维与磷石膏结合机理主要是磷石膏基体和短切玄武岩纤维之间的机械锁合和化学结合。

Effect of Chopped Basalt Fiber on the Bending Strength of Phosphogypsum

In this paper, the influence of chopped basalt fiber on the flexural strength of phosphogypsum was studied. The mechanism of chopped basalt fiber reinforced phosphogypsum was analyzed, and the interface of basalt fiber - phosphogypsum was studied by SEM. The results show that the effect of chopped basalt fiber reinforced phosphogypsum is obvious. With the increase of chopped basalt fiber, the reinforcing effect tends to be stable, and the length of 6 mm chopped basalt fiber is better than 12 mm fiber. When the dosage of 6 mm chopped basalt fiber reached 1.6%, the enhancement effect was stable, and the buckling strength was 7.5 MPa and 15.2 MPa respectively, which was 115% and 85% higher than that of blank group. The effect of 6 mm chopped basalt fiber after hydrochloric acid etching treatment was better. When the optimum content was 1.4%, the compressive strength of 2 h and dry resistance strength reached 8.3 MPa and 17.0 MPa respectively, and increased by 137% and 107 % compared with the blank group. The failure mechanism of the chopped basalt fiber phosphogypsum composite is mainly matrix fracture and fiber extraction. The mechanism of basalt fiber and phosphogypsum is mainly mechanical locking and chemical bonding between phosphogypsum matrix and chopped basalt fiber.