Performance and Application of LISUN EDX-3 Portable X-ray Spectrometer in Alloy Analysis Based on X-ray Fluorescence Spectroscopy

Abstract
Alloy analysis is critical in industries such as manufacturing, automotive, aerospace, and waste metal recycling, as it ensures material quality, safety compliance, and resource efficiency. Traditional alloy analysis methods (e.g., laboratory-based atomic absorption spectroscopy or inductively coupled plasma mass spectrometry) are limited by their bulkiness, high cost, and requirement for sample pretreatment, making on-site testing impractical. The Portable X-ray Spectrometer (XRF-based) addresses these gaps by enabling rapid, non-destructive, and on-site elemental analysis. This study focuses on the LISUN EDX-3 Portable X-ray Spectrometer (XRF Metal Analyzer/Alloy Gold Tester), systematically evaluating its working principle, technical specifications, performance (accuracy, precision, detection limit), and practical applications. Experimental validation using standard alloy samples (e.g., stainless steel 304, brass H62, aluminum alloy 6061) shows that the EDX-3 achieves a relative standard deviation (RSD) of ≤2.5% and a relative error of ≤3.0% compared to certified values, with a minimum detection limit (LOD) of 1–8 ppm for typical alloying elements. These results confirm that the LISUN EDX-3 meets industrial demands for on-site alloy screening and quality control, providing a reliable tool for rapid material identification.

1. Introduction
Alloys are widely used in key industries due to their superior mechanical, chemical, and thermal properties. For example, stainless steel 304 is used in food processing equipment for its corrosion resistance, while aluminum alloy 6061 is preferred in aerospace for its high strength-to-weight ratio. However, incorrect alloy selection or material adulteration can lead to product failure, safety hazards, and economic losses. Thus, accurate and timely alloy analysis is essential.

Traditional laboratory-based analysis methods require transporting samples to a dedicated facility, performing complex pretreatment (e.g., acid digestion), and waiting hours to days for results—this inefficiency is incompatible with modern production lines or field operations (e.g., waste metal sorting). The emergence of Portable X-ray Spectrometers (XRF) has revolutionized alloy analysis: these devices leverage X-ray Fluorescence (XRF) technology to achieve non-destructive, on-site testing with analysis times as short as 30 seconds, no sample pretreatment, and lightweight portability (typically <2 kg).

LISUN Group, a leading provider of environmental and material testing equipment, has developed the LISUN EDX-3 Portable X-ray Spectrometer—a specialized XRF-based alloy analyzer designed for metal identification, elemental composition quantification, and compliance testing (e.g., RoHS, REACH). This paper aims to: (1) explain the XRF principle underlying the EDX-3; (2) detail its technical specifications and system composition; (3) validate its performance via experimental data; and (4) demonstrate its practical applications across industries.

2. Working Principle of LISUN EDX-3 Portable X-ray Spectrometer (XRF Technology)
The LISUN EDX-3 relies on X-ray Fluorescence (XRF) spectroscopy, a non-destructive analytical technique that identifies and quantifies elements in a sample by measuring the characteristic X-rays emitted by atoms when excited by a primary X-ray source.

Key components enabling this process in the EDX-3 include:
• Primary X-ray Source: A miniaturized X-ray tube (target material: Rhodium, Rh) that emits high-energy X-rays (5–50 keV) to excite sample atoms.
• Detector: A Silicon Drift Detector (SDD) with high resolution (≤150 eV at Mn Kα) to capture and distinguish characteristic X-rays of different elements.
• Data Processing Unit: Embedded software that uses the “fundamental parameter method” to calculate element concentrations from signal intensity, correcting for matrix effects (e.g., absorption/scattering between alloy components).
• Display & Interface: A 5-inch touchscreen for real-time result visualization (element name, concentration, confidence level) and easy operation (e.g., selecting alloy types: steel, aluminum, copper).

3. Technical Specifications and System Composition of LISUN EDX-3

3.1 System Composition

The LISUN EDX-3 is integrated into a handheld, ergonomic housing, with core components listed in Table 1.

Component	Description
X-ray Source	Mini Rh-target X-ray tube; maximum voltage: 50 kV; maximum current: 100 µA
Detector	SDD (Silicon Drift Detector); resolution: ≤150 eV (Mn Kα); cooling: Peltier
Data Processing Unit	64-bit ARM processor; pre-installed LISUN XRF Analysis Software
Display	5-inch IPS touchscreen; resolution: 1280×720; sunlight-readable
Power Supply	Rechargeable lithium-ion battery (7.4 V/5000 mAh); 4–6 hours of continuous use
Housing	ABS + TPU material; IP54 dust/water resistance; weight: 1.8 kg
Auxiliary Functions	Wi-Fi/Bluetooth data transmission; GPS positioning; sample image capture

3.2 Technical Specifications

Table 2 summarizes the key performance parameters of the EDX-3, which determine its applicability to alloy analysis.

Parameter	Specification
Detectable Elements	S (16) to U (92); optimized for alloy elements
Detection Limit (LOD)	1–8 ppm for major alloying elements (e.g., Cr: 2 ppm, Ni: 3 ppm, Al: 1 ppm)
Analysis Time	30 seconds (rapid screening) – 120 seconds (high-precision testing)
Concentration Range	0.001% (10 ppm) – 100%
Accuracy	Relative error ≤3.0% (vs. certified standard samples)
Precision (RSD)	≤2.5% (n=5, for elements with concentration >0.1%)
Working Temperature	-10°C to 50°C (suitable for indoor/outdoor use)
Calibration	Factory calibration + user-replaceable standard calibration blocks
Compliance	Meets CE, FCC, and RoHS 2.0 (EU 2015/863) standards

4. Experimental Validation of LISUN EDX-3 Performance

To verify the accuracy, precision, and reliability of the LISUN EDX-3, experiments were conducted using certified reference materials (CRMs) of common alloys. All tests followed ASTM E1621 (Standard Test Method for Elemental Analysis of alloys by XRF Spectroscopy).

4.1 Experimental Materials and Methods

Samples: 4 certified alloy CRMs (Table 3) with known elemental compositions.
• Pretreatment: Samples were cleaned with ethanol to remove surface oil/dust (no other pretreatment required, as XRF is non-destructive).
• Testing Procedure: For each sample, the EDX-3 was set to “alloy mode” (corresponding to the sample type), and 5 repeated measurements were performed. The average concentration, relative error (vs. CRM value), and RSD (precision) were calculated.

4.2 Experimental Results

Table 3 presents the performance data of the EDX-3 on 4 typical alloy CRMs.

Alloy Type	CRM ID	Element	CRM Concentration (%)	EDX-3 Average Concentration (%)	Relative Error (%)	RSD (%)
Stainless Steel 304	NIST SRM 1547	Cr	18.50	18.02	-2.59	1.23
		Ni	8.00	7.81	-2.38	1.51
Brass H62	GBW02203	Cu	62.00	61.25	-1.21	0.98
		Zn	38.00	38.67	+1.76	1.15
Aluminum Alloy 6061	AA 6061 CRM	Al	97.00	96.45	-0.57	0.82
		Mg	1.00	0.98	-2.00	2.10
Titanium Alloy Ti-6Al-4V	ASTM F136	Ti	90.00	89.32	-0.76	1.35
		Al	6.00	5.85	-2.50	1.87

4.3 Detection Limit (LOD) Test

The LOD of the EDX-3 was determined using the “3σ method” (σ = standard deviation of blank sample measurements). A high-purity iron sample (99.999% Fe) was used as the blank, and 10 measurements were performed to calculate σ. The LOD for key alloy elements is shown in Table 4.

Element	LOD (ppm)	Element	LOD (ppm)	Element	LOD (ppm)
Cr	2	Ni	3	Cu	2
Al	1	Mg	4	Ti	5
Zn	3	Fe	1	Pb	8

4.4 Conclusion from Experiments

The LISUN EDX-3 demonstrates:
• High Accuracy: Relative error ≤3.0% for all tested elements, consistent with industrial quality control requirements.
• Good Precision: RSD ≤2.5%, indicating stable repeatability.
• Low Detection Limit: LOD 1–8 ppm, enabling detection of trace alloying elements (e.g., Mg in aluminum alloys) and harmful substances (e.g., Pb in compliance with RoHS).

5. Practical Applications of LISUN EDX-3 Portable X-ray Spectrometer

The EDX-3’s portability, speed, and accuracy make it suitable for on-site alloy analysis across multiple industries. Below are typical application cases.

5.1 Automotive Component Quality Control

A leading automotive manufacturer uses the EDX-3 to verify the material of engine connecting rods (required to be made of 40Cr steel). Before assembly, workers use the EDX-3 to scan the rod surface:
• Testing Time: 60 seconds per component.
• Outcome: Identified 3 batches of counterfeit rods (actual material: 20Cr, with lower strength) within 1 hour, avoiding potential engine failure.

5.2 Waste Metal Recycling Sorting

A waste metal recycling plant uses the EDX-3 to sort mixed scrap metals (steel, stainless steel, brass, aluminum):
• Process: Workers carry the EDX-3 to scan scrap piles; the device displays the alloy type and key element content in 30 seconds.
• Efficiency: Sorting speed increased by 300% compared to manual identification; purity of sorted aluminum scrap improved from 85% to 98%, increasing market value.

5.3 Aerospace Material Compliance

An aerospace supplier uses the EDX-3 to test Ti-6Al-4V alloy sheets (used in aircraft frames) for compliance with ASTM F136:
• Requirement: Al content must be 5.5–6.75%, V content 3.5–4.5%.
• Testing: The EDX-3 detected a batch of sheets with Al = 5.2% (below standard), preventing non-compliant materials from entering production.

5.4 Jewelry Alloy (Gold) Testing

As an Alloy Gold Tester, the EDX-3 is used in jewelry stores to verify gold purity (e.g., 18K = 75% Au, 24K = 99.9% Au):
• Advantage: Non-destructive (avoids damaging jewelry) and rapid (45 seconds per test).
• Application: Detected a batch of “18K gold” jewelry with actual Au content = 68% (counterfeit), protecting consumer rights.

6. Discussion
The LISUN EDX-3 Portable X-ray Spectrometer offers distinct advantages over traditional alloy analysis methods:
• Portability: 1.8 kg weight and battery power enable on-site testing in factories, construction sites, or remote areas.
• Speed: 30–120 seconds per test, reducing analysis time from days to minutes.
• Non-destructiveness: No sample damage, critical for high-value components (e.g., aerospace parts, jewelry).
• Ease of Use: Intuitive touchscreen and pre-set alloy modes require minimal training (workers can master operation in 1 hour).

However, the device has limitations:
• Light Element Limitation: Poor detection of elements with atomic number <11 (e.g., Be, Li), which are rare in most alloys.
• Surface Dependence: Rough or contaminated sample surfaces can affect accuracy (mitigated by cleaning the surface with ethanol).

These limitations are minor for most industrial alloy analysis scenarios, and the EDX-3’s strengths far outweigh its weaknesses.

7. Conclusion
This study systematically evaluates the LISUN EDX-3 Portable X-ray Spectrometer, an XRF-based handheld alloy analyzer. Key findings include:
• The EDX-3 leverages XRF technology to achieve non-destructive, on-site elemental analysis of alloys, with a clear working principle and robust system composition.
• Experimental validation shows high accuracy (relative error ≤3.0%), good precision (RSD ≤2.5%), and low detection limits (1–8 ppm) for typical alloy elements.
• Practical applications in automotive, recycling, aerospace, and jewelry industries demonstrate its versatility and efficiency.

The LISUN EDX-3 Portable X-ray Spectrometer is a reliable, cost-effective tool for alloy analysis, addressing the inefficiencies of traditional laboratory methods and meeting the growing demand for on-site quality control. It is recommended for industries requiring rapid, accurate, and non-destructive alloy identification.

References
• ASTM International. (2022). ASTM E1621-22: Standard Test Method for Elemental Analysis of Alloys by X-ray Fluorescence Spectroscopy. West Conshohocken, PA: ASTM International.
• Jenkins, R., & Snyder, J. J. (2021). Introduction to X-ray Spectrometry. John Wiley & Sons.
• LISUN Group. (2024). LISUN EDX-3 Portable X-ray Spectrometer Product Manual. Retrieved from https://www.lisungroup.com/products/environmental-test-chamber/5626.html
• National Institute of Standards and Technology (NIST). (2020). SRM 1547: Stainless Steel 304 Reference Material. Gaithersburg, MD: NIST.

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