| Basalt fiber is a kind of new inorganic fiber. Its production process is environmentally friendly and it has excellent mechanical properties and corrosion resistance properties. In addition, this fiber has good heat insulation and sound insulation performance, and the perfect performance of wave permeability is also its advantage. This article mainly analysis the properties change of basalt fiber after aging in acid,alkali and the relative humidity environment.And the environment is combined with the actual using environment. The SEM, EDS, ICP, FTIR are used to characterize the fiber’s morphology,chemical composition, short-range order degree and molecular structure.Besides, the quality retention rate and tensile strength are used to characterize its quality and mechanical properties. Specific research is divided into the following three parts:First part focuses on the aging study of basalt fiber in the acidic environment.Sulfuric acid and hydrochloric acid were used as the fiber aging medium,which were respectively provided with different concentration and temperature and the test cycle is for 84 days. The results showed that when the temperature is 65℃,the aging time is 84 days and the concentration is 0.1 mol/L.,there are cracks appearing on the fiber’s surface and potassium ion precipitation is the most of all the ions. In the sulfuric acid environment, the potassium ions precipitation in the fiber is as high as 40%, and the precipitation of potassium ions in hydrochloric acid environment is as high as 45%. With the increase of temperature, the precipitation of internal elements in the fiber is also increasing. The filament tensile strength of basalt fiber decreases with the aging time while the fiber weight loss ratio increased. Under the condition of normal temperature, 1mol/L hydrochloric acid and sulfuric acid. Fiber’s highest mass loss rate were for 6% and 5% respectively. The highest intensity change is respectively for 2000 Mpa and 1800 Mpa. The infrared spectrum indicated that the mainly reaction occurs in the acidic environment was for ion exchange among H ~+ and other ions.The second part focuses on the aging study of basalt fiber in alkaline environment.NaOH solution of different concentrations and different temperatures is used. And the saturated Ca(OH)2 solution of different temperatures is used as the aging medium too. The experimental period is for 84 days. In the Na OH medium,results show that when the temperature is 65℃,the concentration is 0.1mol/L,the fiber’s surface is damaged seriously and it became scale.In the saturated calcium hydroxide environment, the surface of the fibers occurred exfoliated layered. And precipitation of sodium ions is the most. The highest precipitation of sodium ions in Ca(OH)2 environment is respectively for 14%. With the increase of temperature, the precipitation of internal elements in the fiber is also increasing. Under the condition of normal temperature, fiber weightlessness is as high as 7% in the saturated calcium solutions; in the 0.1 mol /L NaOH environment, the weight loss reached a maximum of 8%.The highest strength change is respectively for 2000 Mpa and 2200 Mpa. The main reason for the change of the fiber properties in the alkaline environment is that the OH- can damage the structure of the basalt fiber.The third part focuses on the aging study of basalt fiber in distilled water and 95% relative humidity environment. The experimental period was 98 days, and the results showed that the basalt fiber has a small change in damp and hot environment. In the distilled water of 65 ℃, the highest precipitation is sodium ions, and the content is as high as 7.5%. Fiber ’s weightlessness rate reached a maximum of 2%.And the tensile strength decreases as the aging time prolonged. |
PDF Full Text Request