What is HT-PLA / heat-resistant PLA (and PLA-CF) good for?

Use Polymaker HT-PLA when you can anneal the part and you want the annealed heat-deflection numbers. As printed, it is still a PLA-neighborhood plastic. PLA-CF is a different product: abrasive, and not a heat upgrade on Polymaker's own table. Heat, PLA versus PLA+, carbon fiber, and PLA printing are the pages this one should not repeat. Drying has the 60 °C (140 °F) / 6 hour row.

The thermal table

Polymaker's HT-PLA data lists, as printed, HDT of 58.6 °C (137 °F) at 1.8 MPa and 61.4 °C (143 °F) at 0.45 MPa, and Vicat of 156.2 °C (313 °F). Annealed, HDT is 71.7 °C (161 °F) at 1.8 MPa and 107.2 °C (225 °F) at 0.45 MPa, and Vicat is 155.2 °C (311 °F). Glass transition on that sheet is 59.8 °C (140 °F). The intro line "up to 130 °C (266 °F)" is not one of those HDT cells. The product page says "up to 150 °C (302 °F)" and defines heat stability as holding shape while not under a load.

The product page's anneal instruction is 30 minutes at 80–100 °C (176–212 °F), 100 °C (212 °F) recommended, with about 0.3–0.6% dimensional change. The same page then gives a thickness schedule: 30–60 minutes under 4 mm, 1–2 hours at 6 mm, 2–4 hours at 8 mm, and 3–6 hours at 10 mm, cooling in the oven. The TDS page's "3 minutes at 80–90 °C (176–194 °F)" does not match that schedule. The product FAQ also says only the GF version gains significant HDT from annealing, while the TDS table shows the unfilled grade's 0.45 MPa HDT rising from 61.4 °C (143 °F) to 107.2 °C (225 °F). Keep the table, and do not smooth over the FAQ.

HT-PLA lists a nozzle of 210–230 °C (410–446 °F) and a bed of 25–60 °C (77–140 °F), the same window as the product page. It says the unfilled grade is non-abrasive and that a 0.2 mm nozzle is allowed. HT-PLA-GF is the hardened-nozzle row. The product page says it is 12% glass fiber. The glance table lists annealed HT-PLA-GF HDT at 114.7 °C (238 °F) under 0.45 MPa. Polymaker is the brand index. PLA is the material hub.

PLA-CF is the other column

The same glance table lists PLA-CF at 54 °C (129 °F) HDT under 0.45 MPa and Vicat 64 °C (147 °F). PolyLite PLA on that table is 60 °C (140 °F) HDT. PolyLite PLA-CF lists 190–230 °C (374–446 °F), a bed of 50–70 °C (122–158 °F), and a hardened nozzle. Bambu PLA-CF lists the same nozzle and bed and is also flagged hardened. Fiber does not turn PLA into HT-PLA. PETG-CF and PLA-CF is the comparison with the unfilled plastics.

The threads

r/BambuLab 1mevr7y is a toughness test, not an anneal test. The score-7 comment asks for eSUN and ELEGOO PLA+ in the next round. r/BambuLab 10k03sy is layer lines at 0.08 mm. The score-6 comment questions that layer height. The other three links in the bank are a cold-plate question, a PLA Tough substitute, and stuck PLA-CF. They are not HT-PLA, and no excerpt was supplied.

Questions