Additive material properties have the potential to match or be enhanced beyond conventional wrought and cast properties as the structural control of AM evolves. The AM process has been shown to break up reinforcing carbide or oxide agglomerates, which should enhance material properties. On the other hand, AM process build and post-processing parameters need to be closely controlled to eliminate defects such as porosity (gas or process-induced), particle contamination or from previous material runs (e.g., Nb particles in Ti6Al4V), unmelted feedstock particle inclusions, lack of fusion defects, cracks, porosity, high surface roughness, residual stress, warping and undesirable texture.
Proper post-build thermal processing, such as hot isostatic pressing (HIP) and heat treatments, are often required to consistently attain equivalent or superior properties compared to the MMPDS database of statistically-based design values. Castings and jet engine blades are frequently HIP processed to close internal pores and provide fully-dense parts with improved fatigue, creep and toughness properties.
Pressure Technology, Inc. provides HIP services for densifying 3D-printed metal parts. HIP increases fatigue strength of AM parts (see figure 10). On certain alloys, the microstructure in castings or powder metal parts can be refined through aging heat treatments to improve material properties. Surface finish refinement and surface enhancement (shot or laser peening) could be applied after HIP to further enhance fatigue properties.
AM has the potential to create alloys with unique microstructures for structural applications requiring high-performance materials. Recent development in metal AM has resulted in reduced porosity and unique microstructures with enhancing material properties. Future metal additive part integrity will be enhanced through additional work on the development of improved machine reliability, NDE methods for quality assurance, process quality control and process control of feedstock raw materials.
Proper post-build thermal processing, such as hot isostatic pressing (HIP) and heat treatments, are often required to consistently attain equivalent or superior properties compared to the MMPDS database of statistically-based design values. Castings and jet engine blades are frequently HIP processed to close internal pores and provide fully-dense parts with improved fatigue, creep and toughness properties.
Pressure Technology, Inc. provides HIP services for densifying 3D-printed metal parts. HIP increases fatigue strength of AM parts (see figure 10). On certain alloys, the microstructure in castings or powder metal parts can be refined through aging heat treatments to improve material properties. Surface finish refinement and surface enhancement (shot or laser peening) could be applied after HIP to further enhance fatigue properties.
AM has the potential to create alloys with unique microstructures for structural applications requiring high-performance materials. Recent development in metal AM has resulted in reduced porosity and unique microstructures with enhancing material properties. Future metal additive part integrity will be enhanced through additional work on the development of improved machine reliability, NDE methods for quality assurance, process quality control and process control of feedstock raw materials.