## 3 Results  
The process parameters used (Table 1) resulted in high density (>99.9%) samples with no obvious cracking or porosity. Microstructures of each heat treatment condition are shown in Figure 2. It can be clearly seen that the as-built and quenched AM structures closely resembled the quenched wrought structure as each system had an irregular grain shape. In all heat treatment conditions, the AM samples had significantly smaller grain sizes than the wrought samples and irregularly shaped grains. The wrought material had equiaxed grains in the ordered condition and irregularly shaped grains in the quenched condition. Chemistry results are shown in Table 2 and show that the AM material had a much higher oxygen content and a slightly lower vanadium content compared to the wrought materials. The wrought material had 50.4 at.% iron and was therefore stoichiometrically lean in cobalt, while the AM material had 49.6 at.% iron and was therefore lean on both iron and cobalt, but only slightly so for iron. EBSD evaluation of ordered wrought material (Figure 3a) showed equiaxed grain morphology with a grain size of 49.32 \(\pm\) 6.69 \(\upmu\)m and minimal texture or misorientation. AM material showed a significantly smaller grain size of 5.87 \(\pm\) 0.38 \(\upmu\)m and a distorted microstructure with elongated and \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Element** & **Nominal (wt.\%) [17]** & **Wrought (wt.\%)** & **AM (wt.\%)** \\ \hline Carbon & 0.00 & \textless{}0.001 \(\pm\) 0.0003 & \textless{}0.001 \(\pm\) 0.0003 \\ \hline Manganese & 0.05 & 0.029 \(\pm\) 0.0040 & 0.026 \(\pm\) 0.0040 \\ \hline Silicon & 0.05 & 0.040 \(\pm\) 0.0004 & 0.042 \(\pm\) 0.0004 \\ \hline Cobalt & 48.75 & 48.706 \(\pm\) 0.0733 & 49.809 \(\pm\) 0.0733 \\ \hline Vanadium & 2.00 & 1.996 \(\pm\) 0.0046 & 1.720 \(\pm\) 0.0046 \\ \hline Oxygen & - & 0.016 \(\pm\) 0.0001 & 0.047 \(\pm\) 0.0001 \\ \hline Iron & 49.15 & 49.213 \(\pm\) 0.0729 & 48.356 \(\pm\) 0.0729 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Nominal composition of Hiperco 50A and measured chemistry with test precision for wrought and AM material. Figure 1: Ordering and quenching heat treatment schedules. curved grains (Figure 3b,c). Regions of grain growth and altered grain morphology were observed in the AM material after 2 h of ordering (Figure 3b). Tensile test curves for each heat treatment condition can be seen in Figure 4. Figure 4a shows the engineering stress-strain curves for quenched and as-built AM samples, which all showed high levels of ductility. The wrought material showed the lowest strength, followed by quenched AM material and then the as-built AM material. Each material had similar ductility; however, the as-built AM sample showed greater variation in ductility as well as the lower average values. Figure 4b shows the stress-strain curves for the ordered condition for both AM and wrought materials. Both materials showed significantly lower ductility (\(<\)4%) than other conditions, with the AM material showing  
Figure 2: Characteristic microstructures of AM and wrought material in various heat treatment conditions. AM images are on the left and wrought images are on the right. Samples were etched with [PERSON]’s reagent. significantly higher strength. The AM material also exhibited a significant secondary yield point behavior while the wrought material did not. Figure 5 shows the two AM fracture morphologies observed in testing and is representative of the fracture morphologies observed in the wrought material. Microvoid coalescence was observed in the as-built and quenched AM material, as well as the quenched wrought material, indicating ductile rupture, while transgranular cleavage was observed for both materials in the ordered condition. Figure 6 shows the magnetic performance of AM material for various heat treatment conditions. The AM material underperformed in both the as-built condition and the quenched condition, with the quenched condition having the lower magnetic properties.