LESSON 4.2 · 2:12 · CHAPTER 4 · LAYER TIME AND THE WELD
Cooling is exponential
Each equal step of time removes the same fraction of the remaining excess heat, so the first minute matters most.
Predict · at 0:38 in the video
A bead laid at 250 degrees in a 25 degree cell is at 150 after one minute. What is it at two minutes?
About 94 degrees. The excess went from 225 to 125: it kept 0.556 of itself. Another minute keeps 0.556 of 125, about 69.
Further reading
This course is our own. These books go deeper.
- The economics of Big Area Additive Manufacturing, Post et al., Solid Freeform Fabrication Symposium, 2016
- Additively manufactured carbon fibre-reinforced composites: state of the art and perspective, van de Werken et al., Composites Part A, 2020
About the numbers
Simulations in this lesson are our own. Where a number rests on an assumption or a single source, the video marks it with an asterisk and says where it comes from.
Up next · 4.3 · 2:04Healing goes as the fourth root of time