In metal injection moulding (MIM), besides controlling thedimensional accuracy, satisfying the mechanical properties is essential. Themechanical properties are strongly influenced not only by the metal powderproperties, but also by the MIM process. This time, we will introduce ourscientific analysis works for assuring our μ-MIM® quality.
Chemical composition analysis workis not straightforward for metal material. since the specific densitydifference between the metal and impurity, such as oxygen, hydrogen, nitrogenand carbon is large. Even among the metal elements, for example, stainlesssteels contain carefully controlled alloying elements such as chromium and nickel and these element compositions arestrictly complied to the standard. Since these elements exist in widelydifferent concentrations and have different chemical characteristics, we useseveral analytical techniques depending on the requirements.
ICPSpectroscopy
ICP (Inductively Coupled Plasma)spectroscopy is one of the most powerful elemental analysis techniquesavailable today. It is widely used in the metals, semiconductor,pharmaceutical, environmental, and geological industries because it can detectalmost every metallic element from major alloying elements down to ultra-traceimpurities at parts-per-billion (ppb) or even parts-per-trillion (ppt) levels.Here is an example, iron dissolved in water, 1 ppb means 1 μg/L,which is 0.000001 g of iron in 1L of water.
However, ICP analysis isdestructive, time-consuming and importantly the operation requires skills. Forthese reasons, our sintered part inspection we outsource ICP analysis work, ifrequired. On the other hand, we purchase the powder with the mill sheet, whichmust include this ICP spectroscopy results.
Combustioninfrared analysis / Inert gas fusion analysis
Not allimportant elements can be measured by ICPspectroscopy. Carbon, oxygen, nitrogen and hydrogen require differentanalytical methods because they have a significant influence on the MIM processand the properties of the finished components.
During feedstock preparation, metalpowder is mixed with a polymer binder to provide the flowability required forinjection moulding. If the binder is not completelyremoved during the debinding process, residual carbon or othernon-metallic elements may remain in the component, affecting sintering behaviour, dimensional stability andmechanical properties.
To verify that the process isproperly controlled, we perform combustion infrared analysis in-house tomeasure carbon content. When oxygen, nitrogen or hydrogen need to be evaluated,inert gas fusion analysis is deployed. These analytical techniques allow us tomonitor material quality scientifically rather than relying solely ondimensional inspection.
Through a combination of precision moulding, advanced sintering technology andscientific material analysis, our μ-MIM® technology producesminiature, highly complex metal components with excellent dimensional accuracyand reliable material properties. By continuously investing in analyticaltechnologies and manufacturing expertise, we remain committed to providing dependableμ-MIM®solutions for demanding industrial applications.
Employee column
Hello!I'm Sekiuchi from the Production Control, andI've been here for two years.
Mydays are filled with production scheduling and delivery management, but Ialways strive to create smooth and practical production plans by drawing on theexperience I gained on the manufacturing floor in my previous job.
Now,let me introduce what keeps me going—Chiikawa.
Balancingplanning and control at the same time sometimes feels like taking on a FuriousRajang. But thanks to my "Mushroom"—Chiikawa—I can boost my maximum stamina andkeep pushing forward. With μMIM technology in hand... it's time tohunt!
(...as long as there's no overtime that day!😉)
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Conclusion
Cracking, slumping or blistering is commonly observed due to the binder swelling and/or residual stress difference between the surface and interior. It is possible to avoid these problems by selecting appropriate organic solvents and temperature control.
The catalytic deboning uses sublimation of binder, thus it is possible to decompose the binder in relatively short processing time with minimizing the deformation. However, with a strong acidic atmosphere, theapplicable metal material option is limited.
In the sintering process, the necking, which is bridging the metal powders by thermal diffusion, starts at the sintering temperature. Once the necking starts, the shrinking is observed and increases the density, thus before starting the necking reaction, all the organic components should be decomposed and gas between the powders should be removed. In the sintering process, the unwanted chemical reaction, such as oxidation or carbonization, leads to mechanical property loss, therefore a precise atmosphere control with low heating rate at the beginning of the process is required. Also, when it reaches the sintering temperature, some add it vegetal can be evaporated.