Glossary
This page explains terms that are used on this website and related words.
- Automotive and Aerospace Industries
- Electronic Device Industry
- Medical Treatment and Cosmetics Industries
- Chemical and Materials Industries
- Other Industries
| Term | Meaning |
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| Automotive and Aerospace Industries | |
| ISO 16232/VDA 19 | ISO 16232 (issued in 2007) is an international standard preceded by VDA 19 (issued in 2002), a standard made by the German automotive manufacturing industry. Both of these standards are related to controlling the cleanliness of automotive components. |
| Cast hole | Cast holes are one type of casting defect/failure and refer to cavities on or within die-cast surfaces. Examples of cast holes include gapping, gas defects, and sinkage.
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| Cast surface | Cast surface refers to the surface of a die-cast product after it has been cast.
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| Full penetration weld | In a full penetration weld, the groove is formed by cutting the end of the base material at an appropriate angle. It is an "embedding" welding method that uses weld metal to join the base material and the joining material at this groove. The part where the full penetration weld is formed has the same proof stress as the base material. There are many varieties of groove shapes, but commonly used shapes include V and check mark shapes. |
| Metal structure | Metal structure refers to the atomic bonds and crystal structures within a metal or alloy material, which is an assembly of crystal grains.
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| Grain size measurement | Grain size measurement is used to determine the size of the crystal grains that appear in cross sections observed with a microscope. In the United States, grain sizes are evaluated with grain size numbers (a comparative method) by comparing grain sizes against standard diagrams and grain size charts defined by industrial standards such as ASTM E112-13: Standard Test Methods for Determining Average Grain Size.
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| Graphite spheroidisation | Graphite spheroidisation refers to using elements such as cerium, magnesium, and calcium to process molten casted iron, thereby changing the shapes of casted iron graphite from flakes to spheres. Spheroidising graphite reduces its stress concentration, thereby leading to mechanical properties (tensile strength) and impact values (toughness) that are better than flake graphite casted iron (FC). The proportion of sphere-shaped graphite in a material is expressed with its graphite spheroidisation rate.
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| Contamination | Products are contaminated when foreign particles mix into the principle raw materials of the product. |
| Rake surface | A rake surface is a surface from which cutting waste flows out during material cutting due to a chip in the cutting tool. The surface positioned perpendicular to the rake surface is the flank surface. The ridgeline where the rake surface and the flank intersect is the cutting edge. The angle between the reference plane and the rake surface of the cutting tool is known as the rake angle.
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| Penetration defect | Penetration defect is a term that indicates a welding defect and refers to the actual penetration being insufficient compared to the designed penetration. A weld with a penetration defect does not meet the design created on the basis of a strength calculation and, therefore, cannot obtain the intended strength. |
| Flank surface | A flank surface is a surface positioned to prevent unnecessary contact with the finished surface during cutting due to a chip in the cutting tool. The intersection between this surface and the rake surface, which is positioned perpendicularly to the flank surface, forms the cutting edge. The angle between the flank surface of the cutting tool and the cutting surface is known as the clearance angle.
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| Metallurgical failure analysis | Metallurgical failure analysis refers to determining how a metal material fractured by way of investigating the fracture patterns. The primary caused can be determined by considering the material, manufacturing method, and fatigue.
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| Beach mark | Beach marks, also known as shell marks, are one type of fracture pattern seen in the macroscopic observation of metal fracture surfaces.
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| Sinkage | The casting defect that occurs when volume changes upon the solidification of the molten metal in the die-casting process.
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| Corrosion test | Corrosion tests performed on metals refer to the macroscopic and microscopic observation and composition analysis of the areas where corrosion occurs. Typically, the colour and pitting are analysed in the corroded areas.
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| Intergranular corrosion | Intergranular corrosion refers to the phenomenon in which corrosion occurs selectively only at the grain boundaries of a metal material. It occurs due to an increased number of impure carbon compounds in the metal arising from factors such as inappropriate heat treating. Intergranular corrosion may lead to shedding in which crystal grains peel and fall off. In severe cases, this problem may develop into stress corrosion cracking.
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| Grain boundary crack | Grain boundary cracks caused by stress corrosion. The cracks propagate along grain boundaries because of trace elements, segregation, and chromium-depleted layers.
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| Grain size chart | A chart inserted into the field of view of the microscope used to estimate the grain size of metal structures.
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| Electronic Device Industry | |
| Crimp terminal | A crimp terminal is one component of the connectors of items such as wiring harnesses. It is an important part that mechanically bonds the terminal and the wire by making the wire undergo plastic deformation (crimping) with an appropriate tool. |
| Whisker | Whiskers are metal crystals that grow in whisker shapes from the surface of the original metal crystal to the outside. This phenomenon is often seen in tin plating but may also occur on zinc and other such metals. Possible causes of whisker growth include internal stress, temperature cycle, corrosion, external stress, and electromigration. |
| Loader (wafer loader) | A wafer loader is used to transport wafers in a microscope or other such wafer inspection device. There is a trend toward wafers becoming thinner, which has led to the need for their stable transportation. |
| Electromigration | Electromigration is a phenomenon in which defects in material shapes are caused by the movement of the ions in a conductor due to the momentum transfer between conducting electrons and metal atoms. It is also known as a cause of the occurrence and growth of whiskers. This phenomenon occurs to a greater extent when the current density is high and has taken on even greater importance with the miniaturisation of integrated circuits. |
| Crimping | One type of mechanical bonding, using plastic deformation. Because this method can be used to bond together different materials for which welding and heating are not applicable, it is used in connector manufacturing for the application of connecting the sheath and core wire to the crimped connector. |
| PCB failure analysis | The investigation of failures of electronic circuit boards by measuring electrical characteristics and analysing failure locations with a microscope.
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| Packaged PCB | Packaged PCBs are printed circuit boards after the process to bond, electrically connect, and mechanically secure electronic components (the PCB packaging process). There are various methods to use in packaging including IMT (Insertion Mount Technology), where electrode lead terminals are inserted into through-holes on the circuit board and are soldered, and SMT (Surface Mount Technology), where soldering is performed on the surface of the PCB.
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| Packaging defect | Packaging defects occur in PCB packaging and can be causes of non-packaged electronic components, circuit disconnections, and short-circuiting. Typical examples include crazing and measling (which cause the PCB surface to peel off); delamination (which causes separation between the layers of a PCB); solder voids, blow holes, and pin holes; solder balls; solder bridges; solder projections; cold solder joints; component lifting; and component or chip tombstoning (also known as the Manhattan effect).
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| Insulation defect | Insulation defects refer to defects attributable to electricity leakage caused by poor insulation. They are the cause of failures due to factors such as electrical short-circuits.
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| Continuity defect | Continuity defects are one type of electricity transmission malfunction. They are caused by factors such as microscopic friction and wear, the adhesion of foreign particles, corrosion, oxidation, solder bonding abnormalities, and bonding separation.
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| Solder wettability | Solder wettability is a property that indicates how well a solder in its molten state can spread across the binding surface without splattering. Solder wettability greatly affects the bond strength. For example, solder solidifying without being sufficiently spread will lead to a decrease in bond strength during component packaging, resulting in defects such as contact defects and continuity defects. |
| Solder crack | Solder cracks are solder defects that occur or progress due to factors such as fatigue, the passage of time, and the application of stress after solder bonds are formed. If cracks that are initially microscopic grow, the resistance of the bond will increase. There are even cases where solder cracks lead to Joule heat resulting in fire. |
| Solder defect | Solder defects refer to cases where solder has not been applied appropriately. Typical solder defects include solder bridges and excessive solder, which causes short-circuiting. |
| Plating | The technique of depositing metals onto plastics, ceramics, glass, and other materials for the purpose of changing its physical properties.
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| Plating defect | Defects that occur in the plating layer, typically caused by peeling, blisters, or foreign particles.
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| Wiring harness | Products composed of terminals and connectors used to connect equipment and transmit electricity and signals. Wiring harnesses can be used to simplify assembly processes; to prevent connection mistakes; to reduce wear from operation and vibrations; and to provide physical functions such as fire, oil, and noise resistance together with other such environmental resistance. |
| Wire bonding | Wire bonding refers to wiring performed with the PCB pattern and wires by, generally, loading the bare chip (bare die) within an IC or LSI directly onto the PCB. Most commonly this is a procedure carried out within a clean room. It is also called COB (Chip on Board) packaging.
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| Medical Treatment and Cosmetics Industries | |
| Hydrophilic coating | A coating used to lubricate and prevent contamination when submerged in water, typically used on guide wires of catheters.
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| Balloon catheter | A catheter with a balloon on the tip. They are mainly used with the urinary organs and are made of natural rubber latex or silicone.
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| Chemical and Materials Industries | |
| Abrasion resistance test | A test related to the property of friction, commonly used to measure how much wear will occur.
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| Slag inclusion | A defect caused by the impurities failing to rise to the surface and instead solidifying in the molten metal, thereby remaining in the weld metal. This is one type of welding defect that is not visible to the naked eye. |
| SUMP | SUMP is one way to create samples for microscopic observation. It is used to observe the surfaces of objects that are difficult to make into segments. The object under test is pressure bonded to a celluloid sheet softened with solvent. The object under test is then removed after the celluloid sheet dries. The surface structure of the object under test is transferred to the celluloid sheet and can then be observed with a microscope. SUMP is an acronym of Suzuki's Universal Micro-Printing and was invented by Junichi Suzuki. |
| Moulding defect | Moulding defects refer to defects on the surface, in the interior, and in the shapes of resin-moulded (plastic-moulded) products. Typical defects include surface defects such as silver streaks, black streaks, weld lines, jetting, flow lines, cracking, and crazing; shape defects such as burrs, sinkage (sink marks), short shots, and warpage; and internal defects such as voids and internal sinkage. |
| Ceramic capacitor | Ceramic capacitors are passive elements that store and discharge electric charge (electric energy) by way of capacitance. They serve purposes such as coupling, decoupling, smoothing, and filtering in electronic circuits. Conventional ceramic capacitors were inexpensive and had good high-frequency characteristics but tended to have weak temperature characteristics at the capacitance value. Currently, multi-layer ceramic capacitors (MLCCs)—which are compact, inexpensive, and have excellent thermal stability—are most commonly used.
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| Multi-layer film | Films widely used in the packaging of food and medicine. There are various methods for creating multi-layer films, such as pasting multiple layers together or through extrusion. |
| Tribological test | Tests to measure the effect of friction, wear, and surface damage.
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| Fish eye | Fish eyes are small, spherical deposits on the surface of a film or sheet that form because of the failure of materials to mix together. This defect is especially noticeable when it occurs in transparent or translucent resin (plastic). |
| Pimples | Pimples are paint defects that lead to the loss of smoothness in the coating due to foreign particles mixing into the coating and forming projections. Pimples occur when coarse particles are included in the electrodeposition coating and when foreign particles adhere to the coating before the paint is dry to the touch. |
| Film thickness (paint thickness) | Film thickness refers to the thickness of the film (coating) formed by processes such as paintwork, plating, and coating. In paintwork and coating, this is referred to as the paint thickness. |
| Friction test | In a friction test, a test specimen and an interfacing surface are subject to interaction in relative motion to measure the coefficient of friction. There are several ways to measure the coefficient of friction: by measuring the frictional force with a gauge, by measuring and converting the load power of the driving motor, and by calculating from the behaviour of vibration damping by friction. An additional way is to measure the coefficient of friction by calculating the maximum static frictional force based on the angle at which a material placed on a slanted surface starts sliding.
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| Wear test | In a wear test, the wear resistance of a material is measured. It is performed under conditions that closely approximate the actual usage situation, such as by using a lubricant or by ensuring that all the objects under test are dry. The evaluation is then performed by measuring the change in weight of the test material.
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| Dielectric sheet | Dielectric sheets (dielectric ceramic green sheets) are dielectric objects that have inductive characteristics and are used in applications such as multilayer ceramic capacitors (MLCCs). Inserting a dielectric sheet between two electrodes causes polarisation in which the dielectric sheet is separated electrically into positive and negative parts. The static electricity capacitance that can be stored in a capacitor increases proportionally to the permittivity of the dielectric object, so ceramics that have a relative permittivity that matches the application are used.
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| Mould release failure | Warpage or other shape defects due to moulded products remaining in or failing to smoothly release from their mould. |
| Other Industries | |
| Foreign particle analysis | Foreign particle analysis refers to analysis and identification aimed at investigating the characteristics of foreign particles so as to investigate the causes of and prevent the reoccurrence of problems. This analysis and identification are performed by way of appearance observation using a microscope and composition analysis of the foreign particles contaminating a product or material.
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| Binary image processing | Converting an image to only 2 colours. The processing replaces each pixel with white or black, depending on whether the pixel exceeds or falls below the set threshold.
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| Glass PCB | A glass PCB is a thin, small plate of glass that is used as a printed circuit board for forming the elements and other such devices of an electronic component.
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| Glass fracture surface | A glass fracture surface occurs when a piece of glass is fractured. By observing the fracture surface, the fracture direction and start point can be identified and the type and cause of the fracture can be investigated (fractography).
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| Composition analysis | Composition analysis performed in foreign particle analysis refers to using an elemental analysis to investigate the physical properties of the components (foreign particles) that differ from the main materials. However, it is difficult to identify foreign particles if, for example, a product whose main component is protein is contaminated with an insect, which also contains protein. In such situations, appearance observations and analyses using a microscope are also performed.
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| Microcrack | Microscopic scratches that form on the surface of glass during processing. Microcracks cannot be observed by the naked eye and can decrease the strength of glass and lead to cracking.
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| Particle size analysis | Particle size analysis refers to separating, extracting, and performing image analysis on the particles of the target from an image captured by a microscope and from an element distribution diagram. Measurements such as of area, circumference, and diameter and analyses such as of circularity and aspect ratio enable statistical processing and its evaluation.
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