# Temperature Estimation during Pulsed Laser Sintering of Silver Nanoparticles
## 5 Conclusions  
In this contribution, pulsed laser sintering of inkjet-printed Ag NPs lines was conducted. Using the laser power with 276 mW laser power, 100 ms pulse duration, and 1 Hz repetition rate at a scanning speed of 135 \(\upmu\)m/s, a very low Ag NPs resistivity of approximately 3 \(\upmu\Omega\)-cm within 52 s was obtained, which is 1.9 times the bulk Ag resistivity (1.6 \(\upmu\Omega\)). For accurate temperature calculation during pulsed laser sintering of Ag NPs, a numerical model was developed. Our unique algorithm enabled us to store the maximum temperature induced by the previous laser shot avoiding the thermal conductivity drop during the pulse relaxation period. By storing the maximum temperature, the corresponding thermal conductivity value could be stored, which was adopted as an initial condition for the following laser shots. We elaborated on the effects of pulse duration, repetition rates, and scanning speeds on the residual temperature and thermal diffusion length. While longer pulse durations cause longer thermal diffusion lengths, the higher repetition rates produce higher residual temperatures, which can be controlled by increasing the scanning speed.  
The following are available online at [[https://www.mdpi.com/article/10.3390/app12073467/s1](https://www.mdpi.com/article/10.3390/app12073467/s1)]([https://www.mdpi.com/article/10.3390/app12073467/s1](https://www.mdpi.com/article/10.3390/app12073467/s1)), Equation (S1): Convection heat transfer coefficient \(h\) used in the numerical model, where, \(k\), \(L\), and \(Ra_{L}\) are thermal conductivity, characteristic length, and Rayleigh number, respectively, Figure S1: Illustration of a Gaussian beam profile which depicts the chosen beam diameter (270.9 \(\upmu\)m) selected for the pulsed laser operation in comparison to the printed Ag NPs line width of 135 \(\upmu\)m, Figure S2: 3-D model used for the temperature estimation during pulsed laser sintering of inkjet-printed Ag NP line on a glass substrate, Figure S3: Normal reflectivity and absorption length of Ag NPs structures measured by ellipsometry at different sintering temperature, Figure S4: Maximum temperature plots for (a) 100 ms, 1 Hz, 135 \(\upmu\)m/s, 276 mW (b) 10 ms 1 Hz and 135 \(\upmu\)m/s, 276 mW. (c) 10 ms, 10 Hz, 135 \(\upmu\)m/s and 420 mW (d) 10 ms, 10 Hz, 1350 \(\upmu\)m/s and 420 mW (e) 1 ms, 100 Hz, 135 \(\upmu\)m/s and 1.7 W (f) 1 ms, 100 Hz, 1350 \(\upmu\)m/s and 1.7 W.  
Conceptualization, S.-J.M. and A.H.; methodology, Y.-J.M. and H.-L.L.; software, A.H.; validation, H.-L.L.; formal analysis, A.H. and H.-L.L.; investigation, A.H.; resources, J.-Y.H. and H.K.; data curation, A.H.; writing--original draft preparation, A.H.; writing--review and editing, S.-J.M.; supervision, S.-J.-M.; project administration, S.-J.M.; funding acquisition, H.K. All authors have read and agreed to the published version of the manuscript.  
This study was conducted with the support of the Korea Institute of Industrial Technology as \"Development of root technology for multi-product flexible production\" (KITECH EO-22-0006).  
We would like to thank the Higher Education Commission of Pakistan for financial support to [PERSON].  
The authors declare no conflict of interest.