It may be that there is no true product failure. In fact, one important question that may well be asked is: Did a failure really occur? It is possible to have an undesirable event that involves fracture, wear, deformation, or corrosion but that is not really a component failure. For example, discovering a fatigue crack in a 40-year-old structural component, in many cases, may be less of a surprise than finding one that is free from such cracks For these and similar reasons, it is good practice to avoid the use of terms such as failed part, at least until th investigation has revealed strong evidence that a failure has indeed occurred. The terms subject part, subject component, or physical evidence are preferred. It is also good to have an appreciation for what a failure is not The objectives of failure analysis can vary, as suggested by some of the different types of objectives listed in Table 1. Early in every investigation, those with an interest should determine exactly what their objective is or, have no legal obligation to do so, they still, parties have a genuine desire to prevent recurrences,even and timing considerations usually determine the scope of the investigation. Aside from the cost of the investigation itself, a sure answer that comes after repeat failures may be less valuable than a reasonably sound answer before repeat failures Table 1 Objectives in failure analysis Types of objective Possible precipitating situation Product life cycle Product development Demands of the market Prototyping I Product improvement i Warranty costs L Ongoing Assignment of eparations for financial/physical damage or bodily injury or After subject sponsibility death Prevention of recurrence Any After subject event However, despite these various ways of defining objectives and conclusions in failure analysis, it is still fundamentally worthwhile for the knowledge gained. Obviously, success is more satisfying than failure, but experienced practitioners of failure analysis have learned the value of taking the time to extract lessons about both the technical and people-related causes of the failure. When the challenge is to keep learning, every investigation adds to our competence. Often, problems cannot be solved from the same level of understanding in which they are created Thus, failure analysis may often require a keen and inquisitive outlook, which very good and satisfying way to keep learning on a technical, professional, and personal level for an entire career The Failure Analysis Process: An Overview Debbie Aliya, Aliya Analytical Scope and planning The scope of a failure analysis depends on the depth and complexity of the project. Many failure analysts have experienced being told to find the root cause of a particular failure in half an hour! Usually, this is impossible or leads to superficial results. The scope of the investigation must also be targeted toward finding the real root (physical or human) cause of the failure. Root-cause failure analysis has generated much attention in recent years,and it is a good development when the term root cause is given to mean the particular physical or human effect that precipitated or assisted in a failure. Sometimes the term root-cause analysis is misconstrued to mean figuring out whether a component meets a specification. If it does not meet specification, then the lack of conformity to the specification becomes a convenient"root cause. This use of the term is not only superficial but also invalid. Any approach that does not attempt to link the particular physical effect with the particular lack of conformity and its direct expected consequences is not a valid failure analysis approach During the planning stages on the possible scope of an investigation, it is sometimes useful to focus attention on the potential complexity of the problem and on when the physical cause may have occurred. Various categories of complexity are listed in Table 2. These categories of complexity are not exclusive. All failure analysis work must be founded on the physical causes. Sometimes one is asked to determine a cause based on the verbal Thefileisdownloadedfromwww.bzfxw.comIt may be that there is no true product failure. In fact, one important question that may well be asked is: “Did a failure really occur?” It is possible to have an undesirable event that involves fracture, wear, deformation, or corrosion but that is not really a component failure. For example, discovering a fatigue crack in a 40-year-old structural component, in many cases, may be less of a surprise than finding one that is free from such cracks. For these and similar reasons, it is good practice to avoid the use of terms such as failed part, at least until the investigation has revealed strong evidence that a failure has indeed occurred. The terms subject part, subject component, or physical evidence are preferred. It is also good to have an appreciation for what a failure is not. The objectives of failure analysis can vary, as suggested by some of the different types of objectives listed in Table 1. Early in every investigation, those with an interest should determine exactly what their objective is or, more likely, what their objectives are. If the parties have a genuine desire to prevent recurrences, even if they have no legal obligation to do so, they still need to decide how far they want to go toward this goal. Economic and timing considerations usually determine the scope of the investigation. Aside from the cost of the investigation itself, a sure answer that comes after repeat failures may be less valuable than a reasonably sound answer before repeat failures. Table 1 Objectives in failure analysis Types of objective Possible precipitating situation Product life cycle Product development Demands of the market Prototyping Product improvement Warranty costs Ongoing Assignment of responsibility Reparations for financial/physical damage or bodily injury or death After subject event Prevention of recurrence Any After subject event However, despite these various ways of defining objectives and conclusions in failure analysis, it is still fundamentally worthwhile for the knowledge gained. Obviously, success is more satisfying than failure, but experienced practitioners of failure analysis have learned the value of taking the time to extract lessons about both the technical and people-related causes of the failure. When the challenge is to keep learning, every investigation adds to our competence. Often, problems cannot be solved from the same level of understanding in which they are created. Thus, failure analysis may often require a keen and inquisitive outlook, which is a very good and satisfying way to keep learning on a technical, professional, and personal level for an entire career. The Failure Analysis Process: An Overview Debbie Aliya, Aliya Analytical Scope and Planning The scope of a failure analysis depends on the depth and complexity of the project. Many failure analysts have experienced being told to find the root cause of a particular failure in half an hour! Usually, this is impossible or leads to superficial results. The scope of the investigation must also be targeted toward finding the real root (physical or human) cause of the failure. Root-cause failure analysis has generated much attention in recent years, and it is a good development when the term root cause is given to mean the particular physical or human effect that precipitated or assisted in a failure. Sometimes the term root-cause analysis is misconstrued to mean figuring out whether a component meets a specification. If it does not meet specification, then the lack of conformity to the specification becomes a convenient “root cause.” This use of the term is not only superficial but also invalid. Any approach that does not attempt to link the particular physical effect with the particular lack of conformity and its direct expected consequences is not a valid failure analysis approach. During the planning stages on the possible scope of an investigation, it is sometimes useful to focus attention on the potential complexity of the problem and on when the physical cause may have occurred. Various categories of complexity are listed in Table 2. These categories of complexity are not exclusive. All failure analysis work must be founded on the physical causes. Sometimes one is asked to determine a cause based on the verbal The file is downloaded from www.bzfxw.com