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Hydraulic Testing Machine Retrofits and Price Comparison

There are two hydraulic universal testing machine designs. The first uses a single sided ram to apply force and requires gravity for the piston to return home. This type of hydraulic testing machine is the most common and is used for static tests only. A schematic of a ram based hydraulic tester is shown in Figure 1. The second type of hydraulic machine uses a dual acting piston. The dual acting piston design provides control in both the up and down direction and is commonly used for fatigue testing applications.

Viscoelasticity and Dynamic Mechanical Analysis

Viscoelasticity is the property of a material that exhibits some combination of both elastic or spring-like and viscous or flow-like behavior.

Tensile Testing Concepts & Definitions

Tensile tests are used to determine how materials behave under tension load. In a simple tensile test, a sample is typically pulled to its breaking point to determine the ultimate tensile strength of the material. The amount of force (F) applied to the sample and the elongation (∆L) of the sample are measured throughout the test.

Young’s Modulus, Tangent Modulus, and Chord Modulus

This blog post covers the description and determination of Young’s modulus, tangent modulus, and chord modulus. These properties, commonly used for product and material specification, can be calculated by subjecting a specimen to uniaxial force, measuring its stress and strain properties, and generating a stress-strain curve. The accuracy of the modulus determination depends on the precision of the load and strain measurements.

Mechanical Testing of Vascular Stents

With heart disease being the leading cause of death among adults in the United States, vascular stents are a critical medical device in ensuring patients live longer and healthier lives. There are a variety of stents that range in both size and strength for various applications. Mechanical testing of vascular stent involves testing the vascular stent specimens in various modes of failure including bending, torsion, tensile, crushing, abrasion, and fatigue. This blog post covers certain test types and the recommended equipment to test vascular stents.

Shear Testing Essentials

Shear testing produces shear property data for material specifications, research and development, quality assurance, and structural design and analysis. Shear properties can be calculated via different test types including tension, flexion, and compression as well as different test set ups such as the lap shear method, V-notched rail method, short beam method, and more. Click here for the original blog post.

Definitions

Common measurements obtained from a shear test include:

Sheet Metal Tension Testing

Sheet metal forming operations consist of simple bending, to stretching to deep drawing of complex parts. The mechanical properties of the sheet material greatly influence its formability, which is a measure of the amount of deformation the material can withstand prior to fracture. This blog post covers important definitions determining sheet metal characteristics, the test methods, and the equipment used to quantify them.

Jaw Selection for Tensile Testing Grips

Tensile grip jaw selection plays an important role for successful mechanical tests as if specimen slippage between the jaws occurs or if the specimen breaks or tears in the jaw area testing may need to be discarded. This post covers the available jaw surface types for tensile grips and also the operation of quick-change type jaws.

Introduction

Material Testing: Crucial Step in Bridge Development & Engineering Design

Bridge failures underscore the importance of rigorous material testing. The collapse of the incomplete pedestrian bridge at Florida International University on March 2018 is an example where design errors led to growing cracks as described by OSHA.

Although material failure is not the sole reason for bridge failures, it is a crucial step for selecting the right materials, bridge design analysis, and construction testing.

Load Calculator

In our industry, equipment, including universal testing machines and grips and fixtures, are categorized by the maximum force capacity. We have generated an automatic load calculator to help calculate the required forces necessary to test a certain type of material. The calculator can be found here:  https://www.admet.com/calculators/load-calculator/

To use the calculator:

1- Select the specimen geometry. Options include: rectangular, round, tubular, by area.

Lüders Bands Phenomenon in ASTM E8 Tensile Testing

Some metals, particularly annealed low-carbon steel, or mild steel, show a discontinuity when transitioning from elastic to plastic deformation that produces the yield point phenomenon in the stress strain curve.

Wide Width Tensile Testing

Tensile testing is among the most standard tests performed by universal testing machines yet depending on how the test specimen is used in its native environment, setting up the tensile test method is not always straightforward. Wide width tensile testing is a type of tensile testing procedure used with specimens that are prepared with wider width than the standard tensile specimen coupons. This blog posts covers wide width tensile testing, standards outlining wide width testing methods, and the necessary equipment.

Mechanical Testing- Aerospace Materials & Products

In the aerospace industry, testing is critical in successful product development and implementation. Mechanical testing of materials and products used in aerospace applications is governed by strict standards and often require accreditation. The type of testing performed includes tensile, compressive, flexural, fatigue testing, and more.

Automation vs. Manual Control in Concrete Testing

Concrete is one of the most widely used materials around the world. The construction industry is often involved in a wide array of testing which requires a variety of testing equipment. In addition to simple compression testing, testing standards such as ASTM C39, ASTM C109, ASTM C469, ASTM C1609 are among the test methods that can be followed to measure the mechanical properties of a concrete specimen. This blog post covers the mechanical testing of concrete in lab environments, its automation, and ways of achieving it.

Mechanical Testing of Concrete

Automotive Interior- Mechanical Testing

Aesthetics and material durability are closely related in consumer-facing industries such as the automotive industry. In addition to designing an aesthetically pleasing interior environment, developers aim to create an interior with durable components to stand up to long-term use. This blog post covers the different mechanical tests used to ensure automotive interior parts pass the test for aesthetics, quality, safety, and durability.

Textile Strength Testing

Textiles, yarn, thread, fabrics, wool, cotton, and other animal and plant-derived fibers are commonly tested to ensure product quality by assessing the performance of materials and making sure they are acceptable towards proper end-use. This blog post will cover certain mechanical testing methods to test fabric and go over the testing standards.

Full blog post, including the recommended equipment, can be found here.

Biomechanical Testing

Biomechanics & Biomechanical Testing

Full blog post can be found here

Key concepts for medical device design include biomechanics, biocompatibility, and biofunctionality. This post will go over the mechanics of an exemplar biological tissue, the bone, and mechanical testing of biomaterials that are used in developing medical devices and equipment.

Equipment for Bend Testing per ASTM Standards and User-Specific Applications

While it is easy to imagine why bend testing needs to be performed on rigid materials like plastics (ASTM D790) and concrete (ASTM C1609), in reality bend test applications are common in a variety of industries. Universal testing machines equipped with bend fixtures are used to calculate flexural modulus, flexural strength, yield point, and more.

Material Testing in High and Low Temperatures

High or low temperature testing is made feasible by adding an environmental chamber to a universal testing machine (UTM). Environmental chambers come with their own temperature controller and, depending on the system’s compatibility, the temperature settings and recordings may be controlled with the UTM’s controller or software.

Effect of Specimen Geometry on Tensile Testing Results

How do different specimen geometries affect tensile test results?

Stress-Life Fatigue Testing Basics

ADMET CEO and Chief Engineer Richard Gedney's article on fatigue testing applications was published on the Quality Magazine August 2017 issue. 

The article starts with brief descriptions of the four stages of metal fatigue:

Stage 1: Crack Initiation

Stage 2: : Slip Band or Stage 1 Crack Growth

Stage 3: Stage II Crack Growth

Stage 4: Ductile Failure 

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