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Page 4 of 15 Gao et al. J Mater Inf 2023;3:6 https://dx.doi.org/10.20517/jmi.2023.03

In Equations (2) and (3), is the prediction value of the i data, y is the actual value corresponding to it,
th
i
while n is the size of the dataset.

DATA COLLECTION AND PRE-PROCESSING
Data collection
The mechanical properties [including ultimate tensile strength (UTS), yield strength (YS), and elongation
(EL)] of the SLMed alloys do not only depend on the compositions [40-47] and processes [48-54] but also the
testing condition [55-59] . Therefore, in order to study the influencing factors affecting the mechanical
properties of SLMed Al-Si-(Mg) alloy, the compositions [60-62] (i.e., Si and Mg contents), the manufacturing
processes (including laser power [63-65] , scanning speed [66,67] , scanning spacing [68-70] , powder layer thickness [71,72] ,
[73]
[74]
hatching space , and rotation angle ), and the testing direction [75,76] should be considered at the same
time. However, it is quite challenging to analyze data in high-dimensional characteristic variable space, and
the dimension of the characteristic variable thus needs to be reduced. The energy density (Ed) [77-79] is
commonly used to describe the combined effect of laser power, scanning speed, scanning spacing, powder
layer thickness, and hatching space on alloy properties. Ed can be calculated by using the following
equation,

where P is laser powder, v is scan speed, h is hatch space, and t is layer thickness. Besides, the testing
direction and the rotation angle should also be considered during data analysis. The testing direction
describes the test situation. The tensile direction is regarded as 0° when it is parallel to the substrate plane,
while 90° when it is vertical to the substrate plane. Moreover, the rotation angle represents the successive
layer rotation during the additive manufacturing process.

In order to make the dataset more reliable and accurate, the following guidelines were obeyed during the
data collection:

(i) Only the data of Al-Si-(Mg) alloys manufactured by SLM techniques were collected;

(ii) The data reported in the literature must be complete, and all the information on the composition,
process parameters, and mechanical properties should be included;

(iii) If no actual alloy composition was given in the literature, the nominal composition of the alloy was
used instead.

The data sets of as-built SLMed Al-Si-(Mg) alloys, which include 176 pieces of data from 50 publications,
were established in the present work and displayed in the Supplementary Materials. Figure 1A and B shows
[3,4]
the distribution of UTS, YS, and EL for different SLMed Al-Si-(Mg) alloys, mainly including Al4Si ,
Al7SiMg [12,13,24,49-60] , AlSi10Mg [9-11,61-79] , and Al12Si [4,5,14,40-48] . It is clearly observed in the figure that the strength