Recent developments and opportunities in additive manufacturing of titanium-based matrix composites: A review

Using nanoindentation under various strain rates, the mechanical properties of a laser powder bed fusion (PBF) SKD61 at the 800 mm/s scan speed were investigated and compared to PBF H13. No obvious pile-up due to the ratio of the residual depth (hf) and the maximum depth (hmax) being lower than 0.7 and no cracking were observed on any of the indenter surfaces. The nanoindentation strain-rate sensitivity (m) of PBF SKD61 was found to be 0.034, with hardness increasing from 8.65 GPa to 9.93 GPa as the strain rate increased between 0.002 s−1 and 0.1 s−1. At the same scan speed, the m value of PBF H13 (m = 0.028) was lower than that of PBF SKD61, indicating that the mechanical behavior of PBF SKD61 was more critically affected by the strain rate compared to PBF H13. PBF processing for SKD61 therefore shows higher potential for advanced tool design than for H13.

Section: Resultsmentioning

confidence: 99%

“…However, very few studies have dealt with the mechanical behavior of PBF SKD61 using nanoindentation. It is thus necessary to perform nanoindentation tests to probe the creep behavior of the PBF SKD61 and compare it with that of PBF H13 [9,10].…”

Section: Introductionmentioning

confidence: 99%

Comparison of Nano-Mechanical Behavior between Selective Laser Melted SKD61 and H13 Tool Steels

Yun

Nguyen

Choe

et al. 2018

“…The laser power is located on numerator and usually may be changed largely on the numerical value when compared to the scanning speed value (the same situation for powder thickness and hatch distance) located in denominator. So, in the present study, we only changed laser power to study the influence of energy density on the microstructure, mechanical properties of the obtained samples [30]. The laser parameters used in the LAM process were finally determined after a series of pre-experiments, which were summarized in Table 2.…”

Section: Lam Processmentioning

confidence: 99%

Study on Porous Mg-Zn-Zr ZK61 Alloys Produced by Laser Additive Manufacturing

Zhang

Chen

Liu

et al. 2018

This study reports the effect of Zn contents on surface morphology, porosity, microstructure and mechanical properties of laser additive manufacturing (LAM) porous ZK61 alloys. The surface morphology and porosity of the LAMed porous ZK61 alloys depend on the laser energy input. With increasing Zn contents, the surface quality of porous Mg-Zn-Zr alloys became worse, the grains are obviously refined and the precipitated phases experienced successive transitions: MgZn → MgZn + Mg 7 Zn 3 → Mg 7 Zn 3 . The microhardness was improved significantly and ranged from 57.67 HV to 109.36 HV, which was ascribed to the fine grain strengthening, solid solution strengthening and precipitation strengthening. The LAMed porous Mg-15 wt.% Zn-0.3 wt.% Zr alloy exhibits the highest ultimate compressive strength (73.07 MPa) and elastic modulus (1.785 GPa).

“…Traditional processes such as casting or sintering are also used to make TiC-316L composites [10], but it is difficult to solve the uneven dispersion of reinforcing particles [11]. Compared with the traditional moulding method [12], SLM can produce materials with finer cells, while cell refinement can improve the strength and hardness of materials without loss of plasticity [13][14][15][16].…”

Section: Introductionmentioning

confidence: 99%

Microstructure and Mechanical Properties of TiC-Reinforced 316L Stainless Steel Composites Fabricated Using Selective Laser Melting

Zhao

Bai

et al. 2019

TiC/316L stainless steel (316Lss) metal matrix composite parts have been formed using selective laser melting (SLM). In this study, we have investigated the influence of the TiC mass fraction on the microstructure evolution, microhardness, friction properties, wear properties, and corrosion resistance of the TiC/316Lss composites. The results show that the microhardness increased by the addition of the TiC mass fraction. In terms of friction and wear properties, the corrosion resistance initially increased, and then decreased. Compared with the pure 316Lss (298.3 HV0.2), the microhardness of the TiC/316Lss composites, which were formed with 2 wt% TiC, was raised to 335.2 HV0.2, which was a 12.4% increase, while the average friction coefficient was 0.123. The reason for this is that the addition of TiC can effectively refine the cell size, and as the TiC content increases, the refinement effect is more obvious. During the melting process, TiC particles act as nucleation centres, hindering the growth of crystal cells, promoting the formation of the austenite phase, and forming fine equiaxed structures, which increases the strength. However, excessive TiC particles aggravate the spheroidisation during the process of SLM, leading to increased defects, as well as a decrease in density and corrosion resistance.