Zn Vapor Research Articles

Weld quality improvement and porosity reduction mechanism of zinc coated steel using tandem gas metal arc welding (GMAW)

In this study, we present results showing the improved quality of galvannealed steel welds formed under zero-gap lap fillet configuration, using tandem gas metal arc welding (GMAW). Superior external and internal weldment characteristics are found for the optimized tandem GMAW process compared to that of single DC, single CMT, and single DC pulse processes. Geometrical parameters such as leg sizes, penetration depths, throat lengths, and toe angles are also compared and analyzed. High-speed images reveal that as the distance between the leading and the trailing arc is reduced, agitation of the weld pool is promoted, leading to a more effective Zn vapor release process. The mechanism of Zn vapor bubble formation, growth, and release process is scrutinized and compared at the various arc distances. Finally, tensile shear strength test results show that comparable strength to the base material is expected for a total wire feed rate between 7 and 10 m/min suggesting high weld quality in the previously problematic Zn coated steel weldments.

Microstructure and sliding wear behavior of fly ash reinforced dual phase brass surface composites synthesized through friction stir processing

Dual phase brass was reinforced with industrial residue fly ash particles (0–18 vol%) to produce surface composites through friction stir processing (FSP). Micrographs revealed uniformly dispersed fly ash particles. The interface made a strong bond with the brass matrix because of the absence of pores or any undesirable compounds. Fracture of fly ash particles during processing was not evident. FSP and fly ash particles led to the formation of fine grained structure. There was no evaporation of Zn and the dual phase was retained. TEM micrographs showed evidence for interrupted dynamic recrystallization. Fly ash particles helped to slow down the material removal during sliding wear. The composite specimen produced smaller debris and wore in abrasive manner.

Generation of ZnO nanoparticles by chemical vapor synthesis using quenching air

With the increasing interest in manufacturing nano-sized metal particles in large quantities for their numerous applications in industry, medicine and daily life as well as nanotoxicity testing, there is a critical demand to improve methods to generate nanoparticles with controllable nano-size and high number concentrations. Here, a stable method for the generation of zinc oxide nanoparticles (ZnO-NPs), especially for the size below 10 nm, by chemical vapor synthesis (CVS) using quenching air was proposed. The present study found that the oxidation step of Zn vapor in the ZnO-NP formation process is the rate-controlling step. Six conditions were tested with various furnace temperatures, carrier gas and quenching air flow rates in a tubular furnace. The experimental results showed that the quenching air flow rates (1-5 L/min) have a great impact on ZnO-NPs generation and characteristics. The geometric mean diameter of synthesized ZnO-NPs or aggregates was decreased from 15.26 to 3.27 nm, the total number concentration was increased from 2.56 × 107 to 4.28 × 107 #/cm3 and the morphology changed from tetrapod-shaped to isometric-shaped when the quenching air flow rate was increased from 1 to 5 L/min at 1 L/min carrier gas flow rate and 500 °C furnace temperature. The diameter and concentration remained stable with only small fluctuations for 5 h at all test conditions, which is very useful for nanotoxicity testing. The size of ZnO-NPs was decreased below 10 nm when the quenching rate was 11,000 K/s or higher at 1 L/min carrier gas flow rate and 500 °C furnace temperature. The experimental yield of ZnO-NPs was found to be 11.93% at 600 °C furnace temperature and less than 1.5% at 500 °C. The low yield of small ZnO-NPs is mainly attributed to the low conversion ratio of Zn vapor by the oxidation reaction, and convection-diffusion deposition loss of Zn vapor, ZnO vapor and small ZnO-NPs, which needs further improvement for future mass production using CVS method.

The effects of the post-annealing with a Zn cap on the structural and electrical properties of sol-gel derived MgxZn1−xO films

Structural and electrical properties of Al-doped MgxZn1−xO films were improved by post-annealing with supplying Zn vapor. The Al-doped MgxZn1−xO films were deposited on glass substrates by a sol-gel method. The substrates were dip-coated with a precursor solution and were dried on a hotplate at 270 °C for 10 min. This dip-coating and drying process was repeated 10 times, and the Al-doped MgxZn1−xO films were obtained after calcination in air at 500 °C for 1 h. The as-grown films were post-annealed in H2 at 400 °C for 20 min. To supply zinc vapor, a glass slide with a thermally evaporated Zn layer (Zn cap) was put on the sample surface during the post-annealing. The as-grown films had the wurtzite structure with the c-axis perpendicular to the substrate surface, but the intensity of the (002) diffraction peak decreased with increasing Mg content (x). The crystallinity of the films was improved after the post-annealing with a Zn cap, which was observed when x was below 0.1. The resistivity and carrier concentration of the film (x = 0.1) after the post-annealing with a Zn cap was 6.0 × 10−3 Ωcm and 5.7 × 1019 cm−3, respectively. On the other hand, the resistivity of the film (x = 0.1) after the post-annealing without a Zn cap was 6.6 × 102 Ωcm. Transmittance spectra in the visible range were not affected by the post-annealing. The optical bandgap of the film (x = 0.1) after the post-annealing with a Zn cap was 3.41 eV.

Cupric oxide (CuO)/zinc oxide (ZnO) heterojunction diode with low turn-on voltage

The p-n junction is the fundamental form of an electronic semiconductor device. A p-CuO/n-ZnO heterojunction diode was formed by using thermal evaporation and thermal oxidation techniques. Cupric oxide (CuO) films of 300 µm in thickness were obtained by thermal oxidation of Cu foils. Zinc oxide (ZnO) films of 30 µm in thickness were prepared in two process steps: firstly, thermal evaporation of Zn at atmospheric pressure, and then thermal oxidation to Zn films. The p-CuO/n-ZnO heterojunction diode was formed by performing the steps of ZnO deposition on the surface of the CuO films, and completed by deposition of silver electrical contacts on the top and on the bottom sides of the heterostructure. Structural, morphological, and electrical properties of CuO and ZnO were studied by X-ray diffraction (XRD), Raman spectroscopy, Uv–Vis DRS, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Hall effect techniques. Current-voltage (I-V) measurements were performed to the p-CuO/n-ZnO heterojunction diode. Structural characterization to CuO confirmed that pure, crystalline and (111) textured films can be obtained by thermal oxidation of Cu. ZnO films showed a polycrystalline structure without preferred orientation. The band gap of CuO and ZnO were 1.51 and 3.21 eV, respectively. Cross-sectional SEM and TEM images confirmed the formation of the p-CuO/n-ZnO heterojunction diode. Hall measurements confirmed the p-type conductivity of CuO and the n-type conductivity of ZnO. Also, the carrier concentration and Hall mobility of CuO films were 9.54 × 1012 cm−3 and 267 cm2 V−1 s−1, respectively. ZnO films exhibited a carrier concentration and Hall mobility of 3.69 × 1012 cm−3 and 22.18 cm2 V−1 s−1, respectively. The I-V measurement showed that the p-CuO/n-ZnO heterojunction exhibits a low turn-on voltage of about 0.8 V and a breakdown voltage of about 38 V. Electrical parameter such as rectification ratio and ideality factor were also calculated. An energy band-diagram of the CuO/ZnO heterojunction was proposed, where a built-in voltage of 0.57 eV was observed.

Structural, Morphological and Sensor Properties of the Fractal-Percolation Nanosystem ZnO/NiO

ZnO/NiO fractal-percolation nanosystems have been sensitized using a newly developed three-step technology. During the first stage, ionically sputtered Zn vapors have been deposited under near-equilibrium condensation conditions. In the second stage, Zn layers have been oxidized in air atmosphere, and during the final stage, a NiO layer has been deposited onto the ZnO surface using reactive magnetron sputtering. Gas sensor tests have been performed by measuring current–voltage characteristics of the fractal-percolation nanosystems in air containing methanol or methane. It has been shown that the shape of the I–V curve depends on the reactive gas nature, rendering the possibility to differentiate between different gases, which is an important step to increase sensor selectivity.

A vision-based method for lap weld defects monitoring of galvanized steel sheets using convolutional neural network

Zn vapour is easily generated on the surface by fusion welding galvanized steel sheet, resulting in the formation of defects. The present study develops a novel method for automatically detect typical undercuts, pores and burn-through defects from CCD using concepts of Convolutional Neural Network(CNN) and active vision. Four deep learning methods of training a defects classifier using 1) an AlexNet built from scratch, 2) a Visual Geometry Group 16 (VGG16) built from scratch, 3) the output features of the VGG16 network architecture previously trained on the general ImageNet dataset, 4) the convolutional block attention module adaptively refining the intermediate feature map of VGG16 are investigated. To detect the weld defects, laser streak images of different weld defects are collected and two types of data augmentation are used to reduce overfitting caused by the limited training dataset. In the method 1 and 2, the improvement of accuracy by data augmentation is gradually slow. VGG16 model in combination with data augmentation 2 achieve the state-of-the-art performance for defects detection in the galvanized steel sheets lap joint. Transfer learning methods using the output features of VGG16 and attention mechanism methods introducing the convolutional block attention module achieve improved accuracy in the case of a small number of training dataset. And all classifiers have a 100 % recognition rate for good welds. This shows that the method of combining CNN and laser vision is feasible, and this method can be used to record the number and location of typical defects in continuous welds.

Liquid-vapor equilibrium and evaporation rate of Cd-Zn liquid alloy

In this study, LVE (liquid-vapor equilibrium) data of cadmium-zinc system were determined at a pressure of 7.5 Pa. We compare the use of the Redlich-Kister polynomials with the Wilson equation in fitting activities. The LVE for Cd-Zn system in vacuum distillation was modeled using the two models. The results of the two models are reliable, the Redlich-Kister polynomials are better than the Wilson equation. The LVE phase diagram is reliable for predicting the process of vacuum distillation for Cd-Zn system. The evaporation rates of the elements in Cd-Zn alloy were experimentally measured and calculated by the Langmuir equation. The experimental data on the evaporation of pure metals Cd and Zn are included. The evaporation coefficients of zinc and cadmium under vacuum conditions were calculated. The deviations were discussed. Comparing the calculations with the experimental results, it can be found that the trend is consistent. The activation energies of Cd and Zn in the Cd-Zn alloy under experimental conditions were also calculated.

Bimetallic Ni–Zn/TiO2 catalysts for selective hydrogenation of alkyne and alkadiene impurities from alkenes stream

This study investigates the alternative of replacing noble metals by base metals as catalysts for selective hydrogenation of polyunsaturated hydrocarbons. Nickel catalysts are active for this type of reaction, but poorly selective. However, former calculations anticipated that Ni–Zn alloys could have higher selectivity to alkenes than monometallic Ni depending on the Ni/Zn atomic ratio in the alloy. In this contribution, Ni–Zn alloy nanoparticles supported on TiO2 are synthesized as catalysts for selective hydrogenation of acetylene and butadiene. The designed catalysts with 0.5 wt% Ni loading and various Ni/Zn nominal ratios are prepared by deposition–precipitation with urea (DPU). STEM-HAADF imaging coupled with EDS analysis reveals that Ni–Zn bimetallic particles are formed after reduction treatment at 450 °C. Alloying Ni with Zn leads to a slight increase in the average particle size and a broadening of the size distribution compared to monometallic Ni. However, the average Ni/Zn atomic ratio measured by EDS in the bimetallic particles is always higher than the nominal one, which could be due to Zn evaporation under the beam. The results of acetylene hydrogenation show that although the catalytic activity is slightly reduced after alloying Ni with Zn, the selectivity to ethylene is enhanced from 50% up to 85%, at the expense of the formation of oligomers (coupling products). However, the bimetallic Ni–Zn catalysts suffer from progressive deactivation in this reaction. During butadiene hydrogenation performed in the presence of an excess of propene, the bimetallic Ni–Zn/TiO2 catalysts are significantly more stable, with a high and constant selectivity to butenes (> 95%), compared with Ni/TiO2, which deactivates rapidly in the first hours. Some hypotheses concerning the observed differences in catalytic stability are discussed.

Efficient pore engineering in carbonized zeolitic imidazolate Framework-8 via chemical and physical methods as active materials for supercapacitors

Pore structure of active material plays important roles on energy storage of supercapacitor (SC), since charges are accumulated in and released from pores during charge/discharge process. Carbonized zeolitic imidazolate framework-8 (ZIF-8) with high surface area and electrical conductivity is widely applied as active material. Easy removal of Zn and ZnO simplifies pore engineering of carbonized ZIF-8. It is the first time using chemical and physical methods to create pores in carbonized ZIF-8. Chemical method is removing ZnO and Zn using HCl treatment, and physical method is evaporating Zn at 1000 °C. Due to larger size of ZnO and lower annealing temperature without Zn evaporation, carbonized ZIF-8 synthesized using 800 °C shows the highest specific capacitance (CF) of 186.79 F/g at 20 mV/s, while that prepared using physical method merely presents CF value of 43.82 F/g. With HNO3 and H2SO4 treatments, carbonized ZIF-8 shows reduced electrochemical performance due to serious structure damage. Symmetric SC composed of optimized carbonized ZIF-8 electrodes presents CF value of 214.8 F/g at 20 mV/s and maximum energy density of 10.71 Wh/kg at power density of 800 W/kg. Excellent charge/discharge cycling stability is achieved with CF retention of 83% and Coulombic efficiency of 90% after 8000 times charge/discharge process.

MOF-assisted synthesis of Ni, Co, Zn, and N multidoped porous carbon as highly efficient oxygen reduction electrocatalysts in Zn–air batteries

It is an urgent demand to develop cost-effective and efficient non-noble metal electrocatalysts for oxygen reduction reaction (ORR), the key cathodic reaction of fuel cells and metal–air batteries. In this regard, we herein propose a one-pot strategy to produce porous carbon electrocatalysts multidoped by nickel (Ni), cobalt (Co), zinc (Zn), and nitrogen (N). Typically, appropriate metal precursors are aged with 2-methylimidazole in methanol to obtain Ni and Co co-doped Zn-based zeolitic imidazolate frameworks (Ni-Co-ZIF-8) for the final formation of Ni, Co, Zn, and N multi-doped porous carbon (Ni-Co-Zn-N-PC) through pyrolysis, in which cavities and pores are created because of the Zn evaporation at high temperature, while the Co-N bonds in Ni-Co-ZIF-8 could be inherited. The cavities, Co-N active sites and additional synergies among different metals that improve the electrical conductivity of the catalyst collectively promote the ORR catalytic performance of Ni-Co-Zn-N-PC. In specific, the as-prepared Ni-Co-Zn-N-PC features favorable ORR electrocatalysis in a half-wave potential of ca. 0.864 V, limited current density of ca. 6.40 mA cm−2, superior long-term stability, and strong anti-interference to methanol. In addition, a zinc–air battery using Ni-Co-Zn-N-PC as air-cathode catalyst exhibits good performances in terms of open-circuit voltage, power density, specific capacity, and durability, suggesting its promise in practical energy conversion devices.

Forming quality, mechanical properties, and anti-inflammatory activity of additive manufactured Zn-Nd alloy

Zinc (Zn) has recently been recognized as a promising bone repair material due to its inherent biodegradability and favorable biocompatibility. In this work, rare earth neodymium (Nd) was introduced into a Zn-based alloy fabricated using a laser powder bed fusion (LPBF) process. Results showed that addition of Nd significantly improved the melt fluidity and reduced the evaporation of Zn, thereby achieving parts with a high densification rate of 98.71%. Significantly, the Nd alloying treatment effectively refined the grain size from 25.3 to 6.2 µm. NdZn5 eutectics precipitated and contributed to a second-phase strengthening effect. As a result, the tensile strength increased to (119.3±5.1) MPa and the Vickers hardness to (76.2±4.1). Moreover, the Zn-Nd alloy exhibited good anti-inflammatory activity, as the Nd ions released during degradation had a strong affinity with cell membrane phospholipids and consequently inhibited the release of inflammatory cytokines. It also presented favorable cytocompatibility, showing great potential as a bone repair material.

In-situ formation of Zn oxide particles in CuZn matrix during friction stir processing

Cu–30Zn plates were friction stir processed at a rotational speed of 1120 rpm and a traverse speed of 50 mm/min. Two kinds of samples were produced. The first sample was friction stir processed without using a secondary phase. In the case of the second sample, Al2O3 particles were incorporated into the Cu–30Zn plates to produce a surface nanocomposite. In the absence of Al2O3 particles, the produced sample showed the typical microstructures of friction stir processed brass alloys. However, in the presence of Al2O3 particles, the SZ showed a bimodal grain structure, and Zn oxide particles were formed. The high heat input condition of FSP caused the evaporation and scape of Zn from the CuZn matrix. The evaporated Zn reacted with oxygen of the air entrapped between the Al2O3 particles, which formed in-situ and encapsulated Zn oxide particles. This phenomenon has not been yet reported in the literature.

An experimentally-determined general formalism for evaporation and isotope fractionation of Cu and Zn from silicate melts between 1300 and 1500 °C and 1 bar

Vaporisation fractionates elements and their isotopes between condensed phase(s) and the gas phase according to two end-member regimes; kinetic (Langmuir) or equilibrium (Knudsen). The fractionation factor of isotopes i and j of element E between gas and liquid, i/jE(αvap-liq), in the former case depends only on the molar masses of the evaporating species, (Mj/Mi)0.5, whereas, at equilibrium, the fractionation factor is ∼1 at high temperatures. The prevailing regime depends on the production rate of vapour species relative to their rate of transport away from the evaporating surface, for which an accurate theory is lacking. Here, we present results of Cu and Zn isotope fractionation during evaporation of ferrobasaltic melts in the FeO(T)-CaO-MgO-Al2O3-SiO2 (FCMAS) system in a 1 atm gas-mixing furnace at oxygen fugacities (fO2) from 10−8 bar to 10−0.68 bar (air) at temperatures between 1300 and 1500 °C. In air, the fractionation factors are 65/63Cu(αvap-liq) = 0.9972 ± 0.0001 and 66/64Zn(αvap-liq) = 0.9959 ± 0.0002, but increase under reducing conditions, at logfO2 = −8 for 65/63Cu(αvap-liq) (0.9979) and at −3, −5.5 and −8 for Zn, at which 66/64Zn(αvap-liq) = 0.9967, 0.9974 and 0.9978, respectively. This behaviour is caused by slow elemental diffusion through the silicate melt relative to the rate of evaporative loss, thereby depressing i/jE(αvap-liq). When evaporation rates far exceed those for diffusion in the melt, no isotopic fractionation develops in the condensed phase. To account for the 65/63Cu(αvap-liq) and 66/64Zn(αvap-liq) values observed in air, we develop a formalism for mass transfer applicable to any evaporating species over a range of pressures, gas compositions and flow regimes. For natural convection at 1 bar, diffusive transport through the gas is the rate-limiting step, where D(i,j)k is the diffusion rate of isotope i or j through a gas with mean molar mass Mk. Under these conditions i/jE(αvap-liq) is proportional to (Dik/Djk)2/3, and not (Dik/Djk) as previously proposed. Our model predicts i/jE(αvap-liq) in other experiments, and in nature, to a precision of ±0.0005 assuming ideality. The fractionation factors inferred for moderately volatile elements in lunar mare basalts (>0.9994) are inconsistent with a mass transport process, and instead reflect near-equilibrium conditions of vapour loss from the Moon.

Sub-nano tungsten nitride (WN) loaded on N-doped porous carbon as efficient catalyst for oxygen reduction reaction

Herein, tungsten nitride (WN) doped porous carbon (W-CN0.1) with sub-nano level was designed as efficient electrocatalyst for ORR after selectively evaporation of low boiling-point Zn at pyrolysis temperature of 900 ℃ and in-situ reducing of W precursor in ‘cage’ of ZIF-8. Benefiting from more exposed active sites, W-CN0.1 containing sub-nano WN exhibits better catalytic activity in comparison with W-CN0.2 loading dense WN nanoparticles, including more positive half-wave potential (-0.099 V) and higher electron transfer number (3.98). Moreover, the as-synthesized sub-nano WN has good methanol tolerance (vs Pt/C) and long-term stability.

A Comparative Study of the ZnO Growth on Graphene and Graphene Oxide: The Role of the Initial Oxidation State of Carbon

The role of the oxidation state of carbon on the early stages of growth of metal oxides was studied for the particular case of ZnO deposition on graphene and graphene oxide on SiO2 (G/SiO2 and GO/SiO2, respectively) substrates. The growth was carried out by thermal evaporation of metallic Zn under an oxygen atmosphere at room temperature. This technique permits quasi-equilibrium conditions during the oxide growth, allowing the characterization of the fundamental interaction between ZnO and the graphene-based substrates. Although in both cases ZnO follows a Volmer–Weber growth mode controlled by nucleation at defects, the details are different. In the case of the GO/SiO2 substrate, the nucleation process acts as a bottleneck, limiting the coverage of the complete surface and allowing the growth of very large ZnO structures in comparison to G/SiO2. Moreover, by studying the Zn-LMM Auger spectra, it is shown how the initial nature of the substrate influences the composition of the ZnO deposit during the very early stages of growth in terms of Zn/O atomic ratio. These results are compared to those previously reported regarding ZnO growth on graphite and graphene on Cu (G/Cu). This comparison allows us to understand the role of different characteristics of graphene-based substrates in terms of number of defects, oxidation state, graphene support substrate and number of graphene layers.

Zeolite imidazolate framework-8 derived molybdenum carbide/nitrogen-doped carbon for highly-efficient hydrogen evolution reaction

A metal-organic framework-derived method was developed to synthesize highly efficient non-noble metal electrocatalyst for alkaline hydrogen evolution reaction (HER). Zn2+, phosphomolybdic acid were coordinated with 2-methylimidazole, and zinc (Zn) and phosphorus (P) species were removed by annealing at 850 °C in N2 atmosphere, resulting in micro/mesoporous molybdenum carbide (Mo2C) composited with nitrogen-doped carbon (denoted as ZIF8-xMo-850). The optimized sample ZIF8-12Mo-850 displayed a low overpotential of ~85.7 mV to deliver a current density of 10 mA cm−2, with a corresponding Tafel slope of ~69.7 mV dec−1 in 1 M KOH. This HER catalytic activity was competitive with the most recently developed Mo2C-based HER electrocatalysts. From further investigation, the high HER catalytic activity of ZIF8-12Mo-850 is owing to three aspects: (i) The appropriate Mo feeding amount of ZIF8-12Mo-850 resulted in the highest surface content of Mo2+ active site; (ii) The evaporation of Zn and P in the ZIF8-12Mo precursor formed its largest average pore diameter of 32.3 nm, which leaded to the highest electrochemically active surface area (ECSA) of 64.29 cm2 (iii) The 2-methylimidazole in the precursor resulted in the highest surface content of pyridinic N in ZIF8-12Mo-850 (14.63%), which efficiently improved its conductivity and charge transfer efficiency.

Influence of Nucleation Conditions on the Structure of Zinc Oxide Films

The temperature conditions of nucleation of ZnO films on surface-oxidized silicon substrates during magnetron sputtering of a cermet ZnO–Zn target in an Ar atmosphere and chemical vapor deposition in a hydrogen flow upon Zn and H2O vapor interaction have been investigated. It is shown that the rate of zinc desorption from a growing surface increases significantly and the film growth is suppressed at a substrate temperature above 450°C. It is revealed that two-step deposition with preliminary low-temperature sublayer formation is necessary for ZnO film formation at high temperatures.

Bimetallic ZnCo zeolitic imidazolate framework/polypyrrole-polyaniline derived Co/N-doped carbon for oxygen reduction reaction

Non-noble-metal based materials with high activity for oxygen reduction reaction (ORR) are urgently required to substitute Pt-based materials. Herein, metallic Co/N-doped carbon electrocatalysts were synthesized via a facile pyrolysis method of bimetal ZIF(ZnCo)/polypyrrole-polyaniline (ppy-pani) precursors. The evaporation of Zn and the introduced ppy-pani can lead to the porous structure and effectively hinder the aggregation of Co species, which results in the small nanoparticles uniformly distributed on carbon matrices. A high ECSA and a high content of Co species are obtained after the introduction of ppy-pani, thus resulting in the abundant Co2+ species to enhance ORR. Therefore, the optimized ZIF/ppy-pani-750 exhibits a high E1/2 (~0.86 V) and a low Tafel slope (~43.6 mV dec−1).

Process-Dependent Composition, Microstructure, and Printability of Al-Zn-Mg and Al-Zn-Mg-Sc-Zr Alloys Manufactured by Laser Powder Bed Fusion

Additive manufacturing (AM) technology for metallic alloys such as laser powder bed fusion (LPBF) brings tremendous opportunities for development of novel alloys specifically designed for AM that would desensitize the inherent process variability and requires a refined understanding of processing–structure–property relationship that would contribute to future alloy development. In this study, two different alloys, Al-6Zn-2Mg and Al-6Zn-2Mg-0.7Sc-0.3Zr in wt. pct, representing traditional and AM-specific novel aluminum alloys, respectively, were manufactured by LPBF technique using pre-alloyed gas atomized powders. The Al-Zn-Mg ternary alloys exhibited cracks at various LPBF processing parameters, primarily along the grain boundaries of the large columnar grains that extended across multiple melt pools. The severity of cracking in LPBF Al-Zn-Mg alloys was process-dependent and could be correlated to the change in alloy composition due to evaporation of Zn and Mg with high vapor pressure. The Scheil–Gulliver non-equilibrium solidification calculations showed that the Al-Zn-Mg alloys with lower Zn and Mg concentrations had smaller solidification range (i.e., ΔT) and steepness values (i.e., $$ \left| {{\text{d}}T / {\text{d}}f_{\text{s}}^{1/2} } \right| $$ near $$ f_{\text{s}}^{1/2} = 1 $$), which corresponded to a lower cracking severity. On the other hand, no cracks were observed in Al-Zn-Mg-Sc-Zr alloys, although their solidification range and steepness values were similar to the ternary Al-Zn-Mg alloys. The microstructure of Al-Zn-Mg-Sc-Zr alloys exhibited a much refined heterogeneous microstructure containing small equiaxed and columnar grains within each melt pool, owing to the heterogeneous nucleation upon primary Al3(Sc,Zr) particles. Process-dependent microstructure was observed as a result of variation in thermal gradient and cooling rate associated with LPBF parameters. Findings from this study provide guidance for the future design of AM-specific aluminum alloys and insights into the microstructural control by LPBF.