Tomaz Brajlih, Matej Paulic, Tomaz Irgolic, Ziga Kadivnik, Joze Balic and Igor Drstvensek
This paper aims to present a comparison between selective laser sintering and injection moulding technology for the production of small batches of plastic products.
Abstract
Purpose
This paper aims to present a comparison between selective laser sintering and injection moulding technology for the production of small batches of plastic products.
Design/methodology/approach
The comparison is based on analysing the time–cost efficiencies of each manufacturing process regarding the size of the series for the selected product sample. Both technologies are described and the times and costs of those individual processes needed to create a final product are assessed when using each of the manufacturing processes.
Findings
The study shows that the time-cost efficiency of the selected laser sintering technology increases according to the complexity of the product and decreases with increasing series size and product volume.
Research limitations/implications
The study and absolute values of the presented results are limited to a selected plastic product, but the series size-focused efficiency analysis could be expanded to general cases.
Originality/value
The presented analysis could be used as a general guideline for a decision-making process regarding the more efficient manufacturing method. In addition, the results show the viability of using selective laser sintering during the early stages of production when fast product availability is required, regardless of the series size. Also, some complementary effects of using both technologies in the serial production of the same part are discussed.
Details
Keywords
Tomaz Brajlih, Urska Kostevsek and Igor Drstvensek
One of the main problems of selective laser sintering (SLS) manufacturing process is the dimensional accuracy of products. Main causes of dimensional deviations are material…
Abstract
Purpose
One of the main problems of selective laser sintering (SLS) manufacturing process is the dimensional accuracy of products. Main causes of dimensional deviations are material shrinkage and size of laser heat affected zone (LHAZ). This paper aims to present a new method of adapting SLS manufacturing shrinkage and LHAZ compensation parameters to the geometrical characteristics of processed parts to improve their accuracy.
Design/methodology/approach
The first part of this work presents a hypothesis asserting that the shrinkage and the LHAZ size depend on geometrical properties of products. A method that defines geometrical properties by numerical influence factors is described in the continuation. A multi-factorial experiment with adaptable test part is set up. Then, test builds are manufactured on an SLS machine and measured with a three-dimensional optical scanner. Afterwards, the results are analysed in relation to the presumed hypothesis.
Findings
The analysis of variance of multi-factorial experiment proves the hypothesis and the influence of the geometrical properties on the accuracy of the SLS manufacturing process. Afterwards, a part is manufactured with adapted values of compensation parameters and the archived accuracy is discussed.
Research limitations/implications
Presented research is limited on a single SLS material. Also, some numerical factors are directly linked to the build volume dimensions of the SLS machine that was used in the experiment. However, results can be generalised and some guidelines for shrinkage and LHAZ compensation method are presented. Also, some guidelines for future research are proposed.
Practical implications
Based on the presented results, it can be determined that using constant shrinkage and LHAZ values on an SLS machine will not yield the same results in terms of accuracy if the geometrical properties of parts change significantly.
Social implications
By correctly adapting compensation values, the overall achievable accuracy of the SLS process can be achieved, enabling a more reliable production of mass-customised end-user parts such as customised medical accessories and devices for example.
Originality/value
A similar method of numerically describing geometrical properties of part in regard to SLS and directly adapting shrinkage and LHAZ compensation values to them for every individual build has not yet been proposed.