Influence of oxygen in the production chain of Cu–Ti-based metallic glasses via laser powder bed fusion

Figures & data

Table 1. Process conditions during gas atomisation used for powder synthesis.

Alloy	Purity	P (MPa)	Tgas (K)	Inert gas	D (mm)	ΔTm (K)	${\dot{m}}_G$(kg h^−1)	${\dot{m}}_L$(kg h^−1)	GMR (–)	d50,3 (µm)
Vit101	CP	1.2	293 (RT)	Argon	2	∼500	592	149	4.0	52
Vit101Si								150	4.0	50
Vit101SiSn								150	3.9	47
Vit101	HP	1.6	293 (RT)	Argon	2.5	∼500	780	152	5.1	44
Vit101	HP-remelted	1.6	293 (RT)	Argon	2.5	∼500	780	146	5.3	38

Vit101 = Cu₄₇Ti₃₄Zr₁₁Ni₈, Vit101Si = Cu₄₇Ti₃₃Zr₁₁Ni₈Si₁, Vit101SiSn = Cu₄₇Ti₃₃Zr₁₁Ni₆Sn₂Si₁, CP = commercial purity, HP = high purity, HP-remelted = re-atomised HP feedstock, p = Atomisation gas pressure, T_gas = Initial gas temperature, RT = Atomisation gas at ambient temperature, D = Nozzle outlet diameter, ΔT_m = Superheated melt temperature, $\dot{m_G}$ = Gas mass flow rate, $\dot{m_L}$ = Melt mass flow rate, GMR = Gas-to-melt mass flow ratio, d_50,3 = Mass median particle diameter.

Table 2. PBF-LB/M fabrication parameters.

Laser power (P)	Scan speed (v)	Layer thickness (d)	Hatch distance (h)	Volume energy density (Ev)	Gas
60 W	1800 mm s^−1	20 µm	70 µm	23.8 J mm³	Argon

Figure 1. Optical micrographs of additively manufactured samples, showing the cross-section along the build direction of (a) HP Vit101 and its representative; (b) EDX result; (c) HP remelted Vit101; and CPs (d) Vit101; (e) Vit101Si and (f) Vit101SiSn.

Figure 2. EMP composition elemental mappings of Oxygen for (a) HP Vit101; (b) HP remelted Vit101; and CPs (c) Vit101; (d) Vit101Si and (e) Vit101SiSn. The colour scale bar is attributed to all results.

Figure 3. Oxygen uptake along the production chain of Cu–Ti-based metallic glasses via laser powder bed fusion using HP and CP feedstocks.

Figure 4. DSC Scans of CP powders of varied class sizes (<20 µm, 23–63 µm, > 63 µm) containing different oxygen concentrations of (a) Vit101 and (b) Vit101Si alloys.

Figure 5. SEM images of the main steps regarding TEM lamella preparation of (a–d) powder and (e–f) PBF-LB/M samples of CP Vit101 alloy.

Figure 6. Representative high-resolution TEM of CP Vit101 (a) powder (20–63 µm) and (b) additively-manufactured sample evidence the lack of (nano-)crystallisation and cluster formation, indicating a fully amorphous phase formation.