At the end of summer 2017 we decided to dedicate a plant completely to the research of new alloys and new parameters for sintering metals. After a few months, we are ready to discuss the experience and reasons why an AM Production Factory cannot do without investing resources in R&D.
"Launching a research and development department was a choice dictated by the market in order to continue to be the partner that finds the perfect solution in a project, along with the customer, for the application of what allows industrial production through additive manufacturing. There are many possibilities already offered by manufacturers, but for critical applications, there is still a wide margin of customization for both the alloy and the printing parameters"
- Pasquali, General Manager
When it is necessary and how research takes place
The research and development centre is activated either upon specific request from a customer or as a result of a broader analysis of what we consider to be the market requirements.
In the first case, we get in touch with the customer, who realizes that there can be many advantages in using additive technologies in terms of lightening, or simply for quicker fulfilment of job orders compared with elements created through microfusion, but appreciates also that the performance of elements produced with "factory" settings is not appropriate for the project specifications.
In the second case, an alloy for which only an alternative material exists is researched and optimized. Therefore this alternative material is similar, but not identical in mechanical and physical qualities or, more simply, its name is already universally known to the planners.
"We start with the granulometric and morphological analysis of the powders to verify the chemical and physical qualities and check the effective possibility of laser sintering. Then tests are performed in sequence on the parameters to refine the combinations in order to meet the expected characteristics in terms of, for example, mechanical properties, density, weight, or specific heat properties. Efforts are made in order to bring out the values that characterize the alloy while maintaining the balance between the other characteristics under certain conditions."
- Orrao - Technical Department
Tests performed on the materials
Each set of parameters must be validated by real field tests. For each alloy and set of parameters for which a certain type of result is expected, a batch of metal test-pieces is sintered.
In a first phase, the elements undergo static property tests. Gradual stress is applied for fairly long periods to validate the mechanical resistance in terms of traction and yield strength.
In the phase that immediately follows, the hardness is checked and thus the resistance to permanent deformation when faced with continuous, concentrated stress.
For elements produced through additive manufacturing, the verification of dynamic properties is particularly critical.
The resilience test, being more demanding in terms of time and costs, is performed if the previous ones had a positive result and if the objects for which the research is performed need to be subject to similar stress in the field.
Once the indispensable tests have been passed, we are ready to fine-tune the resolution of the problems related to the relative convenience to determine the conditions of the production batch for perfect machining.
"Process optimization is to the advantage of the objective quality of the manufactured product produced in the factory in terms of quality, which means reducing any risk in using the component..
- Torelli - Quality Manager
Post process and thermal treatment
The last phase of alloy perfecting takes place through thermal treatment.
When confirmation is obtained from the stress tests, the alloy can be further optimized by subjecting the batch of test-pieces to thermal treatment.
The procedure may have two different purposes: general or specific.
In the first case, the component is stabilized, reducing, for example, the internal tensions and obtaining a general increase in mechanical performance.
In the second case, targeted and vertical operations are performed on specific properties, often at the expense of other features, to make the object, and thus the alloy it is made of, even more ideal to adapt to the purpose for which the research and development was begun.
"An item made through the additive manufacturing of the metals, if properly researched and optimized through the R&D centre in our factory, has the same identical characteristics of a piece machined from solid or one obtained through the use of other traditional production technologies"
- Pisciuneri - Sales Manager