We offer a range of services to Industry. Please see the tabs below for further details or get in touch if you have a specific project in mind.

 

 

 

Be it producing micron, or sub-micron, scale structures on metal surfaces or etching images onto glass, in the laser Lab we have the facilities capable of meeting almost all of your needs. All of our lasers will mark surfaces and are suited to different applications:

  • CO2 laser markers: Particularly well suited to marking or structuring polymers, our CO2 lasers are also capable of engraving some metals, glasses and ceramics.
  • Picosecond laser: Excellent at producing fine micron-sub-micron structures on metallic on inorganic based materials. Ultra-short pulse lasers typically produce very fine features that are virtually free of melt-damage. Whilst unsuitable to processing many polymer types due to most polymers having low absorbance at wavelengths ~1 μm, by adding a colour absorbing additive to the polymer, or by coating it in another material (e.g. carbon or a metal) the material can be made compatible with the laser.
  • Nd:YAG laser: With a pulse width of a few nanoseconds this laser will produce less melt, and therefore cleaner marks, than CO2 lasers, however, the pulses are not short enough to ‘cold-process’ in the way a picosecond laser can. With frequency doubling and tripling the wavelength of light emitted by the laser can be changed making it possible to mark a range of materials. Combining the laser with specially produced masks allows for photolithography or masked processing which is capable of producing a variety of different surface structures.
  • Fibre laser: Whilst predominantly a cutting tool, the fibre laser is more than capable of producing structures on metals and ceramics. The ability to operate in cw, pulsed and modulated modes make this laser capable of a variety of tasks.

(left) Slate engraved using a 50 W CO2 laser and (right) Laser induced Periodic Surface Structures (LIPSS) created in stainless steel


For more details or a quote please e-mail: s.hodgson@chester.ac.uk

A common usage of laser based technology. Lasers can be used to cut, drill and weld anything from metals to plastics. Laser processes offer a contact-free, high precision, highly repeatable process with no wearing parts.

  • Fibre laser: With its specially designed cutting head, our 300W fibre laser offers a precision cutting/welding tool for most materials. The ‘through the lens’ CCTV camera enhance the ability to follow pre-marked paths and our LabView/G-Code controlled xy-stages give excellent control of cutting speed.
  • Epilog Zing series CO2 laser: Whilst this 50 W CO2 laser lacks the power to cut thick sheets of metal, it is very well suited to cutting thin woods and plastics. It can also effectively weld thin plastics together.
  • Picosecond laser: Capable of precisely machining advanced materials (including composites). The ‘cold processing’ of an ultrashort pulse layer helps deal with material mixtures that have differing heat transfer properties.

For more details or a quote please e-mail: s.hodgson@chester.ac.uk

The Laser Lab are proud owners of both a Dataphysics OCA 20 contact angle Goniometer as well as a Dataphysics DCAT 21 Tensiometer for studying the wetting and adhesion properties between surfaces and liquids. Both machines have a selection of options for measuring different material or liquid properties. The OCA 20, in addition to measuring static contact angles and calculating surface free energies, has a tilt stage installed. This enables the measurement of roll-off angles (the angle at which a droplet becomes mobile on a surface) and from these the advancing and receding angles, and thus the hysteresis, can be measured. The DCAT 21 Tensiometer has a range of accessories for measuring liquid properties (Wilhelmy Plate,  Du Noüy Ring, density determination), solid properties (plate/film holder for Wilhelmy-style determination of contact angle, powder holder) and also has the ability to measure the adhesive force of a material.

 

(Left) OCA 20 Contact angle Goniometer (Right) DCAT 21 Tensiometer

Wetting science has been around for centuries and relates to the angle a liquid droplet presents when placed on a surface (low being hydrophilic (wetting) and high being hydrophobic (non-wetting). The steps towards it’s currently recognizable form were taken in the 1800s with the development of the Young equation. By the end of World War 2 the two models most commonly referred to in Wetting today, the Wenzel and Cassie-Baxter models, had been developed. As may be expected, neither of these models tell the whole story and wetting research over the last 20-30 years has focused on developing the understanding of the transition between the two models, how liquids behave in what is called the mixed-state (i.e. somewhere between the two), and the relationship between surface roughness and texture and the contact angle produced. Also, particularly recently, the ability to produce superhydrophobic surfaces (contact angle greater than 150°) has come to the fore. See images below for an example of picosecond laser processing turning stainless steel from a hydrophilic state (left) to a superhydrophobic one (right).

The study of wetting and adhesion is of relevance to a huge variety of disciplines ranging from medical devices and food packaging to lubrication, microfluidics and self-cleaning.

Picosecond laser: Ultra-short pulse lasers are excellent at producing all kinds of nano- and microstructures on surfaces. Often the surfaces created by these structures are extremely hydrophobic. Additionally these lasers can act to polish materials, something that often increases the hydrophilicity of the material.


For more details or a quote please e-mail: s.hodgson@chester.ac.uk

Through membership of the Faculty of Science and Engineering, we have access to an extensive range of materials characterisation equipment. This equipment is readily accessible for commercial activity, and can be found listed below.

Philips CM20 Analytical Transmission Electron Microscope

Transmission electron microscopy (TEM) is a high resolution imaging technique that involves the firing of high energy electrons through a thin (typically ≤ 100 nm) slice of a material. The electrons will interact with the material on their way through allowing for an image to be built up based on the electrons transmitted through the layer. TEM images have a significantly higher magnification than optical microscopes, and as such are able to image down to the nanoscale. TEM’s are also capable of determining the crystallinity of a material (i.e. whether it is amorphous, poly- or monocrystalline).

Custom X-ray Photoelectron Spectrometer

X-ray Photoelectron Spectroscopy (XPS) is a surface characterization technique that provides detailed information of the composition of materials, including atomic%, bonding details and electronic state. XPS works by irradiating a sample with x-rays whilst under ultra-high vacuum. The x-rays are absorbed by electrons in the surface atoms, freeing them from their energy shell. The kinetic energy of the freed electron can be measured and related to the energy of the exciting x-ray to calculate the electron’s binding energy. The binding energy of the electron relates to the element’s electronic configuration and can be used to identify the element and it’s proportion within the material. Neighboring atoms produce slight shifts in these binding energies providing information on it’s chemical bonding. XPS is exceptionally surface specific providing information form only the top 10-20 nm of a surface.

Bruker D8 Advance X-ray Diffractometer

X-Ray Diffraction (XRD) provides a wealth of structural information about materials. By measuring the scattering of x-rays through a material information on the arrangement of atoms within the crystal lattice. It has been used throughout the years in a multitude of fields (there have been 13 Nobel prizes (25 Laureates) awarded for X-ray crystallography), including fault finding (e.g. finding crystalline defects in amorphous material) as well as detecting strain within materials.

Unlike XPS, XRD examines the bulk of a material rather than just the surface.

Scanning Electron Microscopes

(Left) Zeiss Leo 1455VP (Right) Hitachi TM 3030 Bench top SEM

Scanning electron microscopy, similarly to TEM, utilizes the interactions of high energy electrons with surfaces. The most commonly used detectors are secondary electron and backscatter detectors. Secondary electrons are emitted from the surface atoms via inelastic scattering. Because of the surface specific nature of these electrons the images produced using secondary electron detectors are very detailed topographically. Backscattered electrons are high energy electrons that come from the SEM’s electron beam. Due to the fact that heavy elements exhibit stronger backscattering they will also show greater levels of brightness in the resulting image. As such backscattered electron images show differences in chemical composition between areas of a material. Another useful characterization tool is energy-dispersive x-ray analysis (EDX). EDX is able to identify the elemental composition of materials by detecting the characteristic x-rays emitted upon interaction with the electron beam. This provides useful information on the makeup of samples for chemical identification and fault-finding purposes. We have two SEMs on site, a Zeiss Leo 1455VP and a Hitachi TM3030. Both machines can provide EDX analysis and the TM 3030 can also take 3D images for roughness analysis.

Surface Profilometers

 

 

(Left) STIL Micromesure 2 optical profilometer (Right) Form Talysurf Series 2 stylus profilometer

Surface profilers produce detailed images of surfaces. There are two main types, non-contact (i.e. light based) and stylus. From the measured surfaces it is possible to get detailed information about the average surface roughness, layer thickness, grain (or feature) size and peak height. This information can be fed back to industrial manufacturing processes in the form of quality control or can be related to various material or surface properties (e.g. adhesion, light scattering, aerodynamics and friction). Roughness in an incredibly complex phenomenon and, whilst often average roughness (Ra or Sa) is reported. simply reporting the average roughness alone provides insufficient information about the surface. Other parameters, such as Skewness, Kurtosis or peak/valley height, are required in addition to average roughness to give a clearer picture.

Anton Paar Pin-on-Disk Tribometer

 

Tribometers measure the friction and wear of materials. Tribometers can be used to test the effectiveness of lubrication or to simulate the lifetime of machine parts.

SINT Technology RESTAN MTS 3000 Stress Tester

Stresses that remain after the initial instigator of the stress has been removed are known as residual stresses. These types of stresses can be caused by a multitude of ways (e.g. thermal effects, plastic deformations) and can be either intentionally caused or unintentional side effects. As such, the stresses can be beneficial (such as those caused during laser shock peening) or harmful (such as those caused by mechanical fatigue). The MTS 3000 measures residual stresses in materials using the hole drilling strain gauge method.

Optical Microscopes

The oldest of all microscopy techniques, optical (or light) microscopy allows for the rapid surveying of surfaces. Whilst optical microscopes lack the high resolutions of electron microscopes due to their diffraction limit, which is affected by the internal optics and the wavelength of light, they are commonly used at magnifications of ×100 and ×1000 and operate without the need for a vacuum. In the biotechnology labs there are also fluorescence microscopes frequently used for live/dead imaging of bacterial lawns.

Universal Testing Machines

Universal testing machines are used to perform a variety of different tensile or compressive tests on materials. These include 3-point bend (i.e. flex), peel and compression. These tests can be applied to construction materials and packaging for a host of different industries including food, biomedical, semiconductor device and construction. At Chester we have two Instron 3367 and two Instron 3343 machines available for use.


For more details or a quote please e-mail: s.hodgson@chester.ac.uk

Laser shock peening (LSP) has been around since the late 1960s and is a technique by which materials can be strengthened, hardened and have their resistance to wear improved by using high powered lasers to generate shock-waves in a similar manner to mechanical shot-peening albeit one that is contactless. LSP creates beneficial residual stresses in materials, most commonly metals and alloys, by inducing plastic deformation in the material. LSP has applications in aerospace, automotive, medical and military industries amongst others.

  • Nd:YAG laser: In the Laser Lab, we use our Nd:YAG laser for LSP applications. The Q-Smart laser offers pulse energies up to 0.85 mJ, which when focused can offer power densities in the GW/cm2 scale. This is more than capable of providing enough energy to produce the desired effect on most materials that would require peening. The Quantel Q-smart laser can be frequency doubled and tripled to change the emission wavelength to 532, 355 nm respectively.

For more details or a quote please e-mail: s.hodgson@chester.ac.uk

If you are an SME located in the Cheshire and Warrington area then you may qualify for assistance with Research & Development under the new Eco-Innovation project that operates jointly between the University of Chester and Lancaster University. The project works by providing assistance with funding PhD or MSc research students for projects with an Eco-Innovation slant. This could include renewable energy, replacement of toxic materials, lower energy/more efficient processes, recycling of material or improved product lifetimes. If you are interested or desire more information please get in touch.

We currently have a fully funded MRes studentship available:  https://jobs.chester.ac.uk/wrl/pages/vacancy.jsf?latest=00013549


For more details or a quote please e-mail: s.hodgson@chester.ac.uk