Ultim max 100

A field emission scanning electron microscope (FE-SEM; Gemini500, Zeiss, Germany) with energy dispersive X-ray spectroscopy (Ultim max100, Oxford Instruments, United Kingdom), operating at a working distance of 10 mm and 15°keV, was used to observe the precipitation of secondary-phase minerals. SEM specimens were prepared following a method to improve their image resolution and elemental composition (Dong et al., 2003a (link)). The prepared specimens were air-dried for 24 h prior to Pt coating 10 nm in thickness.

The electrospun membranes were examined using an FE-SEM microscope (Apreo 2, Thermo Scientific, Waltham, MA, USA) to evaluate their surface morphology. The samples were sputter coated with gold-palladium (Quorum Technologies Ltd, Q150T S plus, Lewes, UK) for conductivity purposes before analysis. The samples were captured at different magnifications at an acceleration voltage of 20 kV. Elemental analysis of the different electrospun membranes was performed using the EDX attachment of the SEM (Oxford Instruments Ultim Max 100, Abingdon, UK).

We used an energy dispersive spectrometer (EDS) (Ultim Max 100, Oxford Instruments, Abingdon-on-Thames, UK) to conduct a semi-quantitative analysis of carbon (C), oxygen (O), and titanium (Ti) elements in the PEEK matrix after surface polishing to confirm the presence and distribution of the TiO₂ particles for each group. After compression tests, the macroscopic fracture morphology of the PEEK crowns was first visually observed. To assess the fracture characteristics, the fracture surfaces were coated with a 25 nm thick conductive platinum film, and the microscopic fracture morphology was observed using scanning electron microscopy (SEM) (JSM-6500F, JEOL, Tokyo, Japan).

The microstructure
of the samples is characterized by a SEM (IT-500HR; JEOL) instrument
equipped with an EDS detector (Ultim Max100; Oxford Instruments).
To analyze the cross section, the sample is submerged in a glass dish
filled with liquid nitrogen for 120 s and cut along the printing direction
with a scalpel blade. The images were collected in backscattered electron
(BSE) mode under low vacuum (50 Pa). The colormap is built from the
EDS scanning on the cross-sectional surface to analyze the element
distribution.

The macroscopic fracture appearance of the fractured PEEK crowns was observed visually. To observe the microscopic fracture pattern of PEEK crowns, the non-conductive fracture surface was analyzed using a scanning electron microscope (SEM) (JSM-6500F, JEOL, Tokyo, Japan) with secondary electron image mode and 15 kV acceleration voltage after being coated with a thin (~10 nm) conductive platinum film. Meanwhile, an energy dispersive spectrometer (EDS) (Ultim Max 100, Oxford Instruments, Abingdon-on-Thames, UK) with mapping analysis mode was used to analyze the elemental distribution of titanium (Ti), oxygen (O), and carbon (C) on the fracture surface to confirm the dispersion of TiO₂ particles in the PEEK matrix. Furthermore, the crystallinity of the fracture surface was analyzed using a high-intensity X-ray micro-area diffractometer (D8 Discover, Brucker, Billerica, MA, USA) with beam sizes down to 180 × 180 μm² to investigate the crystalline structure of test PEEK crowns. The measured 2θ ranged from 10 to 80°, with a scanning rate of approximately 1° per minute.

The mechanical properties of the fibers were measured using an extensometer (Quasar 2.5 single column, Galdabini, Cardano al Campo, Italy) with a 1 kN load cell with a deformation rate of 3 mm min⁻¹. To measure the magnetic strength of the fibers, a permanent magnet (NdFeB, 35 N grade, 50 × 10 × 5 mm³) was fixed under the top load cell of the extensometer, and placed a fiber measuring 5 cm in length at the bottom of the load cell. The magnet was approached to the fiber until the fiber was adhered to the magnet. We measured this maximum distance and calculated the mean value and standard deviation to define the maximum effective distance as the magnetic strength. The surface elements and topographies of liquid metal and magnetic liquid metal were characterized by scanning electron microscopy (SEM, SUPRA40VP SEM, Carl Zeiss, Oberkochen, Germany) and energy dispersive spectrometry (EDS, Ultim Max 100, Oxford Instruments, Abingdon, UK).