Spray Deposition: A Fundamental Study of Droplet Impingement, Spreading and Consolidation
Abstract
Spray deposition via the Osprey process is rapidly emerging as an attractive technology to produce net or near-net-shaped components of a variety of alloys. The process is schematically shown. The alloy charge is melted under an inert gas cover in a crucible placed on top of the spray chamber. At the appropriate superheat temperature, the molten metal is allowed to exit through a refractory nozzle at the base of the crucible into the atomizing zone. The stream of molten metal is gas atomized. Subsequently, the liquid droplets accelerate and cool/solidify under the influence of the atomizing gas, and consolidate on the substrate to form a homogeneous deposit. Spray deposition has an intrinsic beneficial component of rapid solidification which results in a fine-scale homogeneous microstructure devoid of macroscopic segregation. Further, the process is capable of high throughput rates in excess of 20 kg/min. Key process parameters are superheat, atomizing gas pressure, the working distance and the substrate motion. Detailed descriptions of the Osprey process are given elsewhere.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1988
- Accession Number
- ADA206065
Entities
People
- Alan Lawłey
- D. Apelian
- G. Gillen
- P. Mathur
Organizations
- Drexel University