Test e indagini sui materiali

Failure analysis is performed by systematically examining, testing, and analyzing components to identify the cause and sequence of events that lead to a product failure. This specialized testing can vary significantly depending on the result found.

This process typically involves the following steps:

1. Raccolta di informazioni sul componente, la sua applicazione e la sua storia
2. Esame visivo dettagliato
3. Documentazione fotografica dei componenti e prove visive
4. Controlli non distruttivi
5. Esame stereoscopico a basso ingrandimento o imaging 3D
6. Esame al microscopio elettronico a scansione (SEM) ad alto ingrandimento
7. Spettrometria di analisi elementare/SEM
8. Sezionamento del campione per la microanalisi metallografica
9. Metallografia
10. Prove di durezza
11. Analisi chimica
12. Prove meccaniche
13. Revisione dettagliata delle prove e dei dati
14. Formulazione di una conclusione professionale e di un parere
15. Rapporto interoperatorio dei nostri risultati e raccomandazioni

Corrosion is a chemical reaction phenomenon that results in degradation of material and can lead to serious or catastrophic failures. Corrosion investigation engineering is the process of collecting corrosion failure samples and analyzing them to determine the source (root cause) and severity of the corrosion. Drawing from these analyses, we provide expert opinions and recommendations for corrosion remediation and prevention.

The Rimkus Materials Testing and Investigation team specializes in corrosion investigation engineering and the analytical techniques used to identify corrosion mechanisms. We have the expertise to recommend more corrosion-resistant alloys or coatings for a particular application or environment to prevent recurrent corrosion issues. Our energy dispersive X-ray spectroscopy (EDS) system can analyze corrosion deposits to identify the corrosive agent. We also have the expertise and capabilities to offer accelerated salt fog and other corrosion testing to determine the suitability of materials and coatings for specific environments.

A significant amount of metallurgical engineering is needed to successfully produce sound weldments in mechanical and structural applications.

We can provide welder and welding procedure qualification testing to ensure compliance with a wide variety of industrial specifications such as those set by the American Welding Society (AWS) and the American Society of Mechanical Engineers (ASME).

We perform weld testing to evaluate the soundness, toughness, brittleness, hardness, and other properties of weldments before production begins. Our team also frequently investigates weld failures to determine the root cause of fracture or degradation of the weldment in the field.

Welder and Welding Procedure Qualifications:

• Test di piegatura
• Test di impatto Charpy (CVN)
• Colorante Penetrante Fluorescente
• Ispezione visiva
• Test di macroincisione
• Resistenza alla trazione

Our scanning electron microscope (SEM), with the addition of the energy dispersive X-ray spectrometer (EDS), can examine and analyze samples at magnifications typically ranging from 5X to 20,000X. Using our state-of-the-art scanning electron microscope, our experts can analyze everything from microstructure and fracture surface to corrosion products, pitting, and impurities within the material.

The fracture surface topography revealed at increased magnification can reveal an exorbitant amount of information:

• Tipo di sollecitazione (trazione, taglio, torsionale)
• Modalità di frattura (duttile, fragile, fatica, sovraccarico)
• Direzione di propagazione della frattura
• Area e meccanismo di innesco della frattura
• Contaminazione all'interno della microstruttura
• Analisi elementare di prodotti e depositi di corrosione
• Composizione elementare di parti molto piccole
• Fattori correlati alla produzione o alla riparazione che contribuiscono al guasto
• Altri fattori legati alla causa del guasto

Il laboratorio di prove e indagini sui materiali di Rimkus dispone di due sistemi SEM/EDS commerciali strettamente dedicati all'analisi dei materiali e alle indagini sulla corrosione.

Gli esperti di test e investigazione dei materiali Rimkus utilizzano una varietà di tecniche di test non distruttivi, tra cui:

• Spettroscopia a dispersione di energia (EDS)
  • Microscopia elettronica a scansione (SEM)
• Profilo superficiale 3D ad alta risoluzione
  • Misurazioni del profilo 3D
  • Finitura superficiale/rugosità
• Controllo con liquidi penetranti (PT)
  • Vari tipi di metodi PT liquidi vengono utilizzati per rilevare difetti del materiale aperti alla superficie o per rilevare cricche superficiali aperte. Vengono utilizzati coloranti rossi o penetranti fluorescenti, nonché vari tipi di sviluppatori umidi e secchi.
• Ispezione con particelle magnetiche (MPI)
  • Processo per il rilevamento di discontinuità superficiali e superficiali nei materiali ferromagnetici
• Durezza portatile
  • Rockwell, Brinell, Leab
• Ispezione visiva e a basso ingrandimento
• Spettrometro portatile a fluorescenza a raggi X (XRF)

Metallography is the study of the microstructures of metallic materials. The properties of a material and its performance in a specific application depend on its microstructure. Rimkus utilizes numerous types and magnification of high-resolution optical and digital microscopes during the metallurgical examination process.

Analyses of microstructure in cross-sectioned samples help determine material properties, fracture propagation, corrosion pitting morphology, heat treatment, quality and thickness of plating and coating, grain size, overheat damage, material contamination, flaw characteristics, weld quality, manufacturing design flaws, and defect mechanisms.

The Rimkus Materials Testing and Investigation team has advanced training and knowledge in metallographic preparation procedures/processes, from sectioning and mounting the specimen through the grinding and polishing stages to proper selection and etching techniques of the tested material. Our expert laboratory staff is looked upon to provide metallurgical samples preparation techniques and their subsequent interpretations to clients from across the country.

During manufacturing, defects can be introduced at several stages of processing. Supported by the necessary advanced analytical equipment, expert training, and experience, the Rimkus Materials Testing and Investigation experts perform high level defect investigation to identify the specific processing step in which a defect occurred. Our experts will not only interpret the results but can provide recommendations to prevent future defects.

By providing high-quality defect investigation along with other materials testing methods, our team can determine whether a product failed due to defects or flaws produced in the manufacturing process or if the failure was caused during normal or abnormal usage.

Using a scanning electron microscope (SEM) with an energy dispersive X-ray spectrometer (EDS) is an advanced analytical technique that enables the operator to identify the chemical characterization/elemental analysis of materials. EDS analysis can identify the elemental composition of fine to microscopic particles or larger regions on the surface of samples.

During an SEM examination, the locations, deposits, or areas of interest are analyzed using an EDS attached to the scanning electron microscope. EDS microanalysis is performed by measuring the energy and intensity of the signals generated by a focused electron beam scanned across the specimen.

Elemental Dot Map

Element mapping measures the individual elemental distributions on the exposed surface of a sample. Typically, this technique produces an analysis of one field of view by utilizing the scanning electron beam in conjunction with the EDS detector, in a grid pattern to produce a map. This analysis is particularly valuable when identifying contamination, coating/plating layers, diffusion during welding, and corrosion products.

Rimkus experts have extensive mechanical testing experience to determine the compliance of materials to applicable standards and specifications. We have significant knowledge of mechanical testing methodology and are highly skilled in interpreting the results.

Our team can perform mechanical testing and materials testing as part of a quality assurance program, manufacturing engineering program, failure analysis, or for materials research and development. Tests can be performed to ASTM specifications or other industry-recognized standards.

In-house mechanical testing equipment is used for the following materials tests:

• Test di piegatura
• Prove di trazione
• Test di compressione
• Test CVN (Charpy V-notch)
• Test di microdurezza (Knoop, Vickers)
• Durezza Rockwell
• Durezza Brinell

Il reverse engineering è il metodo per identificare e analizzare i materiali e le lavorazioni utilizzate per fabbricare i componenti al fine di creare prodotti con proprietà identiche. Determinando le proprietà del materiale come la composizione chimica, il trattamento termico, il tipo di rivestimento e lo spessore del rivestimento, è possibile eseguire il reverse engineering.

• Analisi chimica
  • Identificazione della composizione chimica dei materiali
• Valutazione della metallografia/microstruttura
  • Gettare
  • Forgiato
  • Estruso
  • Trattamenti superficiali (nitruro, cementazione, ecc.)
• Trattamento termico
  • Traversa di durezza o microdurezza
  • Profondità effettiva del caso
  • Microstruttura
• Rivestimenti
  • Placcatura
  • Rivestimento
  • Anodizzato, fosfato, rivestimenti di conversione, ecc.

An invaluable component of a failure analysis or corrosion investigation is the chemical analysis of metals. Used for multiple purposes, chemical analysis is crucial in the identification of manufacturing difficulties, completion of quality control requirements, and reverse engineering of components that need to be recreated.

Material chemical composition analysis and verification ensures that each component or raw stock material is produced in accordance with the correct material alloy specification. Chemical composition analysis can be performed using various methods that compare results against the appropriate industry standards, such as ASTM, SAE, and more. Our team of experts routinely analyzes the alloying content of a wide range of materials including, but not limited to iron, steel, aluminum, copper, nickel, zinc, titanium, and lead.

For metals, the Optical Emission Spectrometry (OES) technique utilizes a high-energy spark created between an electrode and a sample of the material to be analyzed. The spark creates an emission of radiation from the excited sample surface with wavelengths characteristic of the elemental chemical composition. The spectrum of radiation is separated into the distinct element lines and the intensity of each line is measured. Finally, these are precisely converted into concentration values for each element present.

OES continues to be the reference technique for direct chemical analysis of solid metallic samples. The unmatched combination of accuracy, high speed, precision, stability, and reliability have made it an indispensable tool for production and verification of quality metal products.

Field metallographic replication is a (semi) non-destructive test required in some applications where it is not possible to remove a component from service or the size of the components prohibits analysis in the laboratory.

Assorted replicating media techniques allow our experts to create a portable copy of the microstructure of interest while in the field. Replication involves removal of the material’s surface by lightly grinding, followed by polishing using fine grits.

Once the surface is properly polished and prepared, it is then etched with various acids to reveal the materials microstructure. The replicating media is then applied and allowed to cure. Once the replicating media is cured, it will be removed from the sample, returned to our laboratory, and analyzed using a variety of microscopes.

Replication can also be performed to replicate surfaces for surface finish or other testing, replicating shapes, corrosion pitting, cracking or any other surface that require imaging or measurements.

With its 6 x 11-inch fully automated stage, the high-resolution Keyence VR enhances our capabilities for measuring and analyzing large samples. It can be utilized in nearly all industries and at every step of engineering, from research and development to production, and from quality control through analysis of failures and defect investigation.

The Keyence VR is just one of the many pieces of advanced technological and analytical equipment we utilize to assist customers in understanding their complex matters.

• Misurazione di profili complessi
  • Keyence VR è in grado di scansionare qualsiasi oggetto o superficie 2D o 3D e di fornire qualsiasi tipo di misurazione di superfici o profili 2D e 3D. Consente inoltre di misurare la finitura superficiale e la rugosità senza contatto e di valutare la planarità reale della superficie.
• Finitura superficiale e rugosità
  • I test di finitura superficiale e rugosità possono essere completati nel nostro laboratorio o in situ in loco, con l'uso dei nostri mezzi di replica ad alta risoluzione e a ritiro zero.
• Difetto del prodotto e adattamento
  • Una guarnizione in gomma è stata installata in modo errato o è difettosa dal produttore? La sede della guarnizione corrispondeva alle dimensioni della guarnizione? Per rispondere a queste domande, possiamo utilizzare le misurazioni del profilo 3D ad alta risoluzione ottenute da Keyence VR.
• Difetti di fabbricazione
  • Possiamo utilizzare Keyence VR per la valutazione di componenti (come i raccordi idraulici) per eventuali cicatrici da usura insolite, linee di stampaggio, deformità, danni alla filettatura o vaiolatura da corrosione.
• Danni ambientali alle coperture
  • I danni ambientali da grandine alle tegole possono essere difficili da caratterizzare e valutare. Con l'uso di Keyence VR, possiamo valutare, caratterizzare e confermare i danni alle tegole canadesi.
• Analisi non distruttiva
  • Le misurazioni 3D del profilo di ingranaggi e boccole sono ora possibili senza controlli distruttivi. Ciò consente ai nostri project manager di valutare i modelli di usura in modo rapido ed efficiente con elevata precisione e ripetibilità.
• Difetti dello stampo ad iniezione
  • Gli stampi e le matrici a iniezione possono usurarsi in modo improprio, causando difetti al prodotto finale. Ora possiamo misurare queste cicatrici da usura e difetti per caratterizzare e identificare le dimensioni degli stampi e delle matrici.