Abstract: Using Z164D as grinding aid， the Bond work index of ball mill experiments and the uniaxial compressive strength experiments of bauxite from Tianyang Guangxi were carried out separately. The results showed that compared with raw ore， the Bond work index of bauxite soaked with water and Z164D solution are decreased by 105% and 379%， and the uniaxial compressive strength are reduced by 2684% and 4279%， respectively. The physical and chemical adsorption between Z164D and bauxite surface are confirmed through the analysis of IR spectra and energy dispersive Xray spectroscopy， and Z164D cannot dip into bauxite inners. A function mechanism model of the effect of Z164D solution on bauxite strength is built， where water and Z164D promote each other to increase defects of bauxite and lower its strength.

Key words: bauxite, grinding aid, Bond work index of ball mill, uniaxial compressive strength, mechanism