Blend Technology With Design to Achieve Innovative Products

Written By Debasish Bhattacharya - Expert in Metallurgy of Precious Metal

Image Courtesy: desktopmetal.com

Traditionally, jewellery is an expression of timeless art, an emotional attachment beyond just adornment. Every design created aims to deliver customer obsession and memorable experience which primarily focusses on the traditional aesthetic expression .

However, in the changing scenario of consumerism, customers seeks disruptive and bespoken designs created with innovation and quality. This is no more a luxury, but a norm. Today’s young generation whose lifestyle has ever shaped the future, are also conscious about sustainability, ethical sourcing , social impact when it comes to buying luxury items including jewellery.

The manufacturers are thus continuously being challenged to deliver collections which meet expectations of the new generation and convert them into loyal customers by paying minute attention to above aspects.

Thus this is a challenging scenario indeed for the designers and manufacturers. With increasing challenges , it is thus pertinent to recalibrate the manufacturing process by adopting new technology and blend it subtly with the creativity.

Technology should be embedded in the manufacturing stream irrespective of the process i.e. be it a casted product or a machined item or a handcrafted artistry . Every technique adopted needs to be well understood from the aspect of metallurgical and mechanical behaviour of the metal during its casting , deformation and refining.

The designer while designing at CAD complimented by rapid prototyping need to be aware about those manufacturing techniques . The collaboration between the designer and the technician is thus an important stage gate process which once crossed will aid in creating the product in an optimised manner meeting all ends.

Let me cite an example of resin casting of bizarre bangle which I observed in one of the manufacturing units in India . That innovative geometry was very complex in terms of metal flow and the designer had used abrupt variation of cross section across the design .

As a result , the solidification pattern during casting was non-directional resulting into repeated casting failures .

Interaction between the designer and the caster helped to achieve help directional solidification with mild modification in sprueing at the CAD and that piece could be casted well . This is a classical example of linking Design with technology .

With introduction of various resins , the aspects of creativity has been revolutionised but at the same time it has added to huge challenges in casting and finishing.

The chemistry and behaviour of the resin under thermal conditions needs to be understood well as its behaviour is drastically different from the traditional wax . Hence, we need to change our investment and burnout parameters accordingly.

The investment chemistry is perhaps least understood in-spite of being the most critical step. Any compromise at the investment and burnout stage will lead to rejection and increased repairs which will make the operation expensive and non-competitive .

Companies spend heavy amounts in buying advanced equipment and consumables, yet they busy mending rejections and repairs. It is primarily because of the poor understanding about material and manufacturing processes. This is an aspect largely ignored in the industry.

Jewellery thus needs to be engineered too , in order to achieve the desired innovation .

Image Courtesy: baj.ac.uk

New technology will open up new design opportunities while the design demands will lead new improved technology such as seen in 3D printing of metal powders , use of composites, use of laser in engraving etc.

But to achieve all above, we need to have a clear understanding about the behaviour of the metal in the given condition and use technology while designing to create innovation.

Also , I would like to mention about the need to focus of using correct technology while recovery and refining of the metal .

Recycling the gold and its use to create a beautiful jewellery adds to the global sustainability drive by reducing the devastating effect on environment and human life caused by mining of gold . Hence, it is a social responsibility to adopt correct techniques and use recycle gold to the maximum.

The refining and recovery should be handled by skilled persons having a knowhow about the chemistry , equations and MSDS of the material being handled .

For example, the technique adopted while refining gold having karat value above 18K and metal having karat value less than 18K are not same. There is a new technology termed ALS available now which has been exclusively designed to handle impurities of the lower karat.

It will help to achieve shorter turnaround time and reduced gold losses with added advantage of being a proven green process.

Recovery of metal from various dust is a more tedious process . It involves various beneficiation techniques followed by pyrometallurgical treatment .

The correct choice between pyrometallurgy and chemical digestion while selecting the recovery method should be based on factors such as metal content, presence of impurity, organics etc.

As an example, the polishing dust from low karat gold process, ideally should be incinerated and smelted before subjecting to refining to get the best yield and purity . I have seen many companies subjecting it to aqua regia digestion after incineration resulting in low yield due to presence of high silver causing passivation.

During refining, the operator must know about factors such as valency change of silver, effect of pH, Redox potential , stoichiometry and equations involved about the process . This will help them to achieve gold with impurities conforming to ASTM B 562 guidelines.

Impurities at ppm level plays big role in increasing repairs and rejections and hence we should control the refining process to get refined gold conforming to above standard consistently .

My observation is that the industry tends to focus on purity of gold only due to lack of proper understanding of the knowhow about the role of impurities.

The choice of equipment such as reactors, furnaces, scrubbers must be done judiciously after thorough understanding of the expectations and capabilities. It will help to get the desired yield, quality with reduced losses and environmental effect.

Thus, thoughtful blending of technology at the design stage aided with proper training is the need of the industry to order to deliver innovative product of high quality and yet stay competitive.

Debasish Bhattacharya