Research on Modification of Steel Fiber in Investment Casting shell

• Published in: International journal of metalcasting Vol. 16; no. 4; pp. 1849 - 1857
• Main Authors: Lü, Kai, Shen, Simin, Ma, Changqing, Li, Yanfen, Liu, Kaixin
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.10.2022
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Materials Science; Metallic Materials; Structural Materials; Technical Paper; steel fiber; reinforcement; heat dissipation; investment casting shell
• ISSN: 1939-5981; 2163-3193
• DOI: 10.1007/s40962-021-00722-4

In this study, different amounts of steel fiber were added in the slurry to prepare fiber reinforced shell with improved performances of investment casting shell. The thixotropy of slurry, as well as green strength, fired strength, high-temperature strength, thermal diffusivity and permeability of the shells were all examined. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to identify morphologies and compositions of the shells. The results showed that the viscosity of the slurry increased with the increase of steel fiber content. The addition of 0.4% steel fiber (3 mm in length) resulted in maximum thixotropic loop of the slurry, and the addition of 0.4% steel fiber (4 mm in length) resulted in maximum green strength of 2.45 MPa, fired strength of 5.82 MPa, and strong enough high-temperature strength. XRD data revealed a shell was mainly composed of Zr(SiO 4 ) and mullite. Also, high temperature led to shell mullitization and sintering. SEM observations indicated that reinforcement steel fiber in the shell was mainly achieved by debonding, deforming, and breaking processes. The addition of fiber led to significantly improved heat dissipation ability and permeability of the shell.