Laser metal deposition additive manufacturing of TiC/Inconel 625 nanocomposites: Relation of densification, microstructu
- PDF / 927,582 Bytes
- 13 Pages / 584.957 x 782.986 pts Page_size
- 51 Downloads / 210 Views
r metal deposition (LMD) additive manufacturing was used to deposit Inconel 625 matrix composites reinforced with nano-TiC particles. The effects of laser energy input per unit length (E) on the densification level, microstructural features, mircohardness, and wear property were investigated. The relatively low E induced insufficient liquid with higher viscosity, thus inhibiting the melted liquid from spreading out smoothly. As a result, a large number of micropores and reduced densification level of LMD-processed parts were obtained. When the E of 100 kJ/m was properly settled, the obtainable densification level generally approached 98.8%. The TiC reinforcements experienced successive microstructural changes from agglomeration to uniform distribution with coarsening grain, as the applied E increased. The nearly fully dense parts using optimal experimental parameters achieved an increased average microhardness of 330 HV0.2, resultant considerably low coefficient of friction of 0.41 and reduced wear rate of 5.4 104 mm3/(N m) in dry sliding wear tests. I. INTRODUCTION
Contributing Editor: Yang-T. Cheng a) Address all correspondence to this author. e-mail: [email protected] DOI: 10.1557/jmr.2015.358
625 superalloy with higher performance is in enhanced demands as aeroengine hot-end components especially in harsher high-temperature environment. Previous investigations showed that ceramic particles reinforced composites can significantly improve the high temperature mechanical properties of the matrix alloy.6 Particles reinforced metal matrix composites have outstanding performances such as superior specific strength, fatigue properties, fracture toughness, wear resistance, and a low coefficient of thermal expansion that are unachievable with conventional materials.7,8 TiC particle is a refractory compound exhibiting the characteristics of high hardness, outstanding thermal stability, wear resistance, and corrosion resistance, and hence being used as a promising reinforcement particles.9,10 The incorporation of TiC particles into the Inconel 625 can obtain even comprehensive improved properties, especially high-temperature properties, e.g., high-temperature creep behavior, hot corrosion property.11–13 Conventionally, the particulate reinforcements in the metal matrix composites are in micrometer scale. The experiments in recent years have proved that when the particle reinforcement size is reduced to the nanometer range, the nano-particles reinforced composites demonstrate even better properties such as higher hardness, strength, wear resistance, creep resistance, and especially excellent fracture toughness.14,15 The conventional micrometer particles reinforced metal matrix composites are far away from possessing such superior performances. Therefore, in this paper, nano-sized TiC particles were incorporated into the metal matrix as reinforcements.
3616
Ó Materials Research Society 2015
Inconel 625 is a solid-solution or/and precipitation strengthened nickel-based superalloy which can work in high temperature and und
Data Loading...
