Supplementary data for the paper: On the origin of start-up effects in ply-ply friction for UD fiber-reinforced thermoplastics in melt
Authors: E.R. Pierik, W.J.B. Grouve, S. Wijskamp, R. Akkerman
	Faculty of Engineering Technology, Chair of Production Technology, University of Twente, Enschede, The Netherlands
	ThermoPlastic composites Research Center (TPRC), Enschede, The Netherlands
	
	Corresponding author: Rens Pierik (e.r.pierik@utwente.nl)

General Information:
This dataset contains the measured ply-ply friction data on UD C/PEEK (Toray TC1200) in melt performed with a friction tester at the University of Twente. 
The data was collected between August and October 2020. The scripts used to process the friction data are included as well.
The dataset contains the supplementary data to a ESAFORM conference paper entitled: 'On the origin of start-up effects in ply-ply friction for UD fiber-reinforced thermoplastics in melt'
 
General purpose:
The general purpose of these experiments is to reveal the underlying principle for the shear stress overshoot observed in transient ply-ply friction tests.
Therefore, a range of different sliding velocities was tested and the pull force with displacement was recorded.
Used specimens are detailed in 'Specimens.pdf', including unique label, material used, test conditions and type of test.

Test equipment:
A bench-marked friction tester with a 1 kN loadcell located at the University of Twente was used to perform the friction tests. A general description of the test procedure
can be found in the document 'Experimental methods friction tests.pdf'. Observations and notes made during the experiments can be found in "Notes on friction tests.pdf", in which 
specimens are referenced by their unique label corresponding to the ones used in 'Specimens.pdf'.

Measured data:
The data was recorded using LABview software and the measured data is organised per specimen, for which the unique lab has been used. 
The following filename convection has been used:
	[material]_[type of test: pp = plyply]_[pressure]_[velocity]_[temperature]_[unique_label].txt
The following data can be found in each file (per column):
	index [-], time [s], normal force bottom left [N], normal force top middle [N], normal force bottom right [N], pull force [N], temperature fixed plate [deg C], temperature moveable plate [deg C], horizontal displacement (4x, broken), vertical displacement [mm]
Matlab R2020a software is used to process the friction data. Matlab scripts per figure corresponding to the ones in the ESAFORM2021 conference paper are included. The force at the end of the measurement
is used to correct the data (zero force). Rheometry data on PEEK 150P was kindly supplied by Marten van der Werff (TPRC). The rheometry data was copied into the script for figure 5a and used subsequently to represent the viscosity of the matrix material.